Halcyon Days ~Sunny Days with Sister-chan~ (v1.0.4) by CatNight
Description
Description:
You wash up on a quiet beach, barely conscious, only to be found and taken in by a kind-hearted nun known only as Sister-chan.
This is a cohabitation touch simulation game that gently unfolds your daily life together under the warmth of spring.
Last update: 2026-05-07
Released: 2025-09-14
Original Name: Halcyon Days ~シスターちゃんと陽だまりの日々~
Creator (developer): CatNight
Translator:
Censored: Yes (Mosaics)
Version: 1.0.4
OS: Windows
Language: English ()
Store:
Genre:
How to install:
Changelog:
Fixed issue where relationship with Sister-chan would become extremely negative when going to town【Bugs and Issues Under Investigation】
Unable to perform insertion during the second forced assaultcreampie not counted when reaching climax simultaneouslyReverts back to calling "older brother"
We apologize for the inconvenience.
v1.0.3
Fixed ending not triggeringFixed fewer choices appearing when climaxing simultaneously from behindFixed Sister-chan remaining asleepFixed remaining asleep when starting touching via "invite to H"v1.0.2
Fixed receptivity being locked at 100Fixed incorrect messages when walking in townFixed items being usable multiple timesFixed 20,000-yen items not working correctlyFixed Mamushi Drink not being releasedFixed character becoming depressed when inviting to HFixed insertion gauge not movingFixed unexpected messages during touch movementAdded wait time to touching to prevent crashes from rapid inputv1.0.1
Fixed screen darkening and progression halt when selecting "time to go home" on a day offFixed ending replaying after waking up in the morningFixed vaginal ejaculation count not increasing beyond one in erotic scenesv1.0
Initial Release
Developer Notes:
Regarding future updates
Hello everyone, this is Ando!
Today, I'd like to express my gratitude to everyone who purchased Halcyon Days ~Sunny Days with Sister-chan~, and share some details about our upcoming update plans.
Message of Gratitude
Thank you so much for playing my very first game. It brings me great joy to see so many people enjoying it, and I must admit, the response has exceeded my expectations. I will continue to work hard to meet your expectations. Thank you again for your continued support.
Future Update Plans
I'm sorry, but we do not plan to offer paid updates. Moving forward, we will focus on providing free updates to make the game even better. The following are the elements we plan to add in future updates:
Touching Scenes
Face-to-face sitting position (during sleep)Cowgirl positionScenario where you wash Sister-chan's body in the bathOral service at the church (may be still images only)Intimate scene at the churchAdditional Character Portraits (Stand Art)
Add standing artwork for the town's sister characterAdd standing artwork for the receptionistAdd standing artwork for Sister-chan in her roomAdditional Still Images
Add ending imagesAdd a scene of peeking into the bathAdd event stills for the town's sister character and the receptionist
Apology Regarding Game Bugs
While we’ve received many kind messages saying things like “Sister-chan is so cute,” we’ve also received numerous reports about bugs in the game. I’m truly sorry that these issues have prevented you from enjoying a smooth gaming experience. To prevent this in the future, I plan to improve our debugging process.
Going forward, I won’t rely solely on my own playtesting. Instead, I’ll also commission freelance testers to conduct full playthroughs and utilize DLsite’s debugging services.
Ideally, I should have done this before the game’s release. However, since this was my first time developing and publishing a game, it didn’t occur to me to seek outside help. From now on, I’m committed to thoroughly improving our debugging efforts to avoid such issues.
Translator Notes:
The game has been re-translated using .
A total of 116 images have been translated.
Default font: Asap Condensed Reguler.
Please enjoy the game, and feel free to share any feedback.
Since the encryption keys for all audio and image assets are different, this English patch will clearly not be compatible with version 1.0.2.
Screenshots
Downloads
Halcyon_Days_ENv1.0.4-93528e.xgames.7z
Related Games
NTR Soccer (v0.1.1) by hizure
Let’s Steal Our Soccer Teammates’ Girlfriends!!“The Golden Door Project”An ambitious initiative that gathers promising soccer players,from all over the country and pits them against each other!Age and background don’t matter. Anyone with potential is welcome!In this soccer-themed NTR game, train yourself, enjoy various activities around town,and deepen your bonds with your teammates… and their girlfriends!Then, use everything you’ve built to seize ultimate victory in the “Golden Door Cup”!Last update: 2026-05-13Released: 2026-05-13Creator (developer): hizureCensored: YesVersion: 0.1.1Language: English, Japanese, Chinese (Simplified)Other Games:Store:Genre:2dcg, 2d game, animated, big ass, big tits, censored, cheating, corruption, creampie, Dilf, groping, japanese game, male protagonist, masturbation, sandbox, sexual harassment, side-scroller, teasing, vaginal sex, voyeurismHow to install:1. Extract and run.Changelog:v0.1.1Initial ReleaseDeveloper Notes:Let's steal one of our soccer teammates!A budding meTuber.She's paying attention to the Golden Door Project as a great opportunity to grow her channel through live streaming and event coverage. Moreover, her boyfriend is Kurosawa Jiku, a key player on the local soccer team, so she's never short of material.However, despite her flashy appearance, she's actually quite shy. This personality trait has hindered her growth as a meTuber.She had just joined the local cheerleading team.These girls are full of energy. They are cheerful and charming, and whenever a soccer match starts, they are always the center of attention.A member of the Golden Door Project staff,She's a woman in charge of scouting and supporting players. Calm, collected, and impeccable at her job, she's relied upon by many. However, it seems she's hiding some ulterior motive...?She's an active girl who jogs around town in the mornings and regularly goes to the gym.She has a straightforward personality, always speaking her mind without any pretense.And she is incredibly proud of her boyfriend, who is currently considered the "strongest" soccer player.That confidence, that pride—the day when it all crumbles at Hiroshi's hands may not be far off.Rin's mother. She is also the wife of a soccer coach and a family-oriented woman who is knowledgeable about nutrition management for athletes.She has a somewhat laid-back and reckless side, which may be due to her upbringing in a wealthy family. However,her seemingly ordinary, happy daily life also begins to unravel little by little.DOWNLOADWin:NTR Soccer is available here as a part of our large adult games collection. Free access to this sex game is available via few clicks. All new games are delivered to you is always here.
NTR Gyaru: The Otaku-Friendly Gyaru Gets Stolen Away [final] by I trusted you and sent you off...
Description:Kanade Yumesaki is a blonde gyaru who sits at the top of the school social caste.As an otaku, I thought she and I belonged to completely opposite worlds.But then—by chance, she spoke to me in the classroom,by chance, we discovered we shared the same hobbies,and our relationship quickly grew closer.Before long, just as we began to harbor faint feelings for each other—like a mutual but unspoken crush—a crack starts to form in our happy days, brought about by the hands of another man…Last update: 2026-05-13Released: 2025-12-20Original Name: NTRギャル -オタクに優しいギャルは寝取られるCreator (developer): I trusted you and sent you off... / 信じて送り出したのに…Translator: (Text) / (Images)Censored: Yes (Mosaics)Version: FinalOS: WindowsLanguage: English (MTL)Store:Genre:2dcg, 2d Game, Male Protagonist, Japanese Game, Censored, Netorare, Male Domination, Vaginal Sex, Big Tits, Exhibitionism, Creampie, School Setting, Animated, Handjob, Blackmail, Rape, Corruption, Oral Sex, Ahegao, Voyeurism, Sex Toys, Footjob, Groping, Humiliation, Group Sex, Internal View, Multiple Endings, Urination, BDSMHow to install:1. Extract and run.Developer Notes:♦Game Overview♦This is a modern-day NTR RPG (similar in format to an ADV).Basic number of CG images: 77There are over 500 CG images with variations.Includes shadow puppet animationOnly moaning sounds are included in the audio.There is no way to avoid NTR (Netorare/cheating).♦Highlights of the H-scenes♦The heroine is slowly seduced by the other man.I'm drawing it carefully.The adulterer never missed an opportunity,He pushes the heroine to her limits, both physically and mentally.In order to corrupt the heroine who refuses physical relations,The lover uses various tactics to make the sexual acts more extreme.Shadow puppetry animation was also used extensively.You can experience a dynamic cuckolding scenario.We've also included erotic scenes with the supporting heroine.♦Here are some H-rated situations♦Having her friend taken hostage, she reluctantly performs nipple licking and handjob.For the purpose of development, only the nipples are persistently played with.Having sex in public of one's own free will to lose one's virginityA silhouette animation of a sensual massage followed by raw sex and ejaculation inside.Public urination play performed solely for the purpose of humiliationShe cancels the protagonist's plans to be embraced by her lover, and indulges in sexual acts at school and in hotels.♦Key Features♦I created a scenario that allows you to feel how real human relationships can fall apart.The common route depicts the innocent relationship between the protagonist and the heroine,Once you enter the designated route, you'll be seduced without a moment's rest.For those who are busy, it is also possible to unlock all flashbacks.There are three different routes available for the cuckolding scenario. You can also choose which route to take.
Shifting Stars (v0.1) by Story Machine Studios
Description:Leon Armstrong is a bio-mechanical engineer for a weapons defense company, Genesis Biotech. Growing up in a military family he is the first not to join the military, opting to focus on martial arts and bio-technology. He finds himself crossing unexpected paths with the enigmatic Danica Thoreson. Two seemingly different people drawn together and thrust into a corporate conspiracy. As they grow closer and their worldviews are challenged they must face a dangerous future. Are we destined by fate or is it truly free will that drives the future forward?Last update: 2026-05-13Released: 2026-05-13Creator (developer): Story Machine StudiosCensored: NoVersion: 0.1OS: Windows, Linux, MacLanguage: EnglishOther Games:Genre:3dcg, Male Protag, Kinetic,How to install:1. Extract and run.Changelog:v0.1initial zone releaseDeveloper Notes:-Kinetic has no choices-Chapters are condensed ala comics/manga/manhwa-Roughly monthly releases-FoW dev cycle takes priority