Summer in Heat is a 3D animated simulator by Miconisomi, built in Unity. It is set in a small rural town where residential streets, fields, and distant mountains meet. You play a man who returns there during midsummer and works as a live-in janitor at his old school during vacation. There he reunites with his niece, who moved after her parents divorced, and her older childhood friend, who stays at school for club activities. Their old closeness has changed, and the story follows how he grows closer to them.
The current release is v1.02, dated July 28, 2025, for Windows. It is available in machine-translated English and Japanese, and it is uncensored. Development is ongoing, as this build includes a changelog. The update added a panty-related interaction and adjusted semen-related visual effects. It also fixed some motion and camera look-at behavior during intimate scenes, improved tail and pigtail handling, preserved settings after restart, added search by name or ID in online custom load, corrected debug mode entry, refined UI behavior, and added a debug option to set all characters to dangerous days. An earlier update improved offline custom character management and message-window display.
Developer's description
Residential areas, farmland, and mountains in the distance. Although it is hardly a remote area
It can never be called a city. It is a country town that can be found anywhere.
Spoiler
The protagonist returns there at the height of summer and takes a job as a live-in temporary worker at his former alma mater.
He takes a job as a live-in janitor during the summer vacation.
There, he meets his niece, Takanashi Takanashi, who has moved there after her parents’ divorce.
Otsuwa (Takanashi Otsuwa), who moved there after her parents divorced,
Rino Akatsuki, her older childhood friend.
Rino Akatsuki, her older childhood friend. Otoha is a transfer student taking remedial classes,
Rino had to attend school during the summer break for club activities.
They used to play together as babysitters in the past.
The relationship between the three reunited girls was not the same as it had been back then, but had changed slightly.
Was it simply because they had grown up, or…?
A chance encounter with Otowa and Rino,
The protagonist begins to develop a special relationship with Otowa and Rino.
Formerly known as "Summer Sacrifice"
v1.02
・Partial motion fixes
・Partial fixes to the look-at function during H scenes
・Implemented panty play (details available on the blog and Ci-en article)
・Adjusted dripping semen effects
・Fixed tail and pigtail behavior
・Fixed settings that reset upon each restart
・Added search functionality (name, ID) to Custom Load (online)
・Debug mode entry method fixed to also allow entry via ‘Right-click held + rapid left-clicks’
・Fixed some UI behavior
・Added ‘Always set all characters to dangerous days’ option to debug mode
v1.01
・Significantly improved the local (offline) management system for custom characters
・Fixed transparency settings for the ADV message window
・Added auxiliary functionality to address ADV message text display issues
・Disabled joystick/controller input
・Fixed display for some models
・Fixed some default color palettes
・Fixed some animations
・Fixed some shaders
・Adjusted some audio
v1.00
- Full version released
v0.14
- Fixed some custom functions
v0.13
- Moved custom data posting destination to reduce server load
v0.12
- Fixed behavior of cross-section animation
- Fixed facial expression bug when loading custom characters
・Some UI fixes
v0.11
・Fixed a crash bug on Radeon series graphics boards
・Some UI fixes
v0.10
・Custom+H trial version released
v0.04
・Added UI to display height and three-size information
・Added a function to take a sub-image to character custom images
・Some UI display fixes
・Some model display and color reflection fixes
・Fixed an area where side hair accessories could not be moved or rotated
・Fixed an issue where the resolution was fixed when starting in full screen under certain conditions
v0.03
・Added a function to view and load submitted custom characters
・Fixed a custom loading bug when using certain OS languages
・Some model fixes
・Some UI fixes
・Fixed unintended behavior when connecting a controller
・Fixed other issues with displaying combinations of clothes, etc.
v0.02
・Added a function to post character customizations
・Added a function to remove the frame rate limit
・Some model fixes
・Some UI text corrections
・Some shortcut key layout changes
・Fixed behavior of side hair tails
・Fixed areas where color changes were not retained
・Fixed clothing and underwear combination issues
v0.01
・Custom trial version released
Player reviews
Player rating5.0 / 5 · 18 ratings
Written reviews18 · avg 4.7★
Positive (4–5★)94%
Latest review2026-03-07
What players say
Most reviewers rate it highly, praising visuals and scenes, while one critic finds little gameplay.
5★15
4★2
3★0
2★1
1★0
Players like
Extensive character customization options
Smooth, detailed sex-scene animations
Attractive anime-style visuals
Smooth performance and flexible UI
Common complaints
Linear story limits player agency
It feels like watching animations, not playing
Occasional UI bugs and janky menus
Best for players who enjoy character customization and detailed adult animations.
Summarised from 18 written player reviews.
aiye26032026-03-07★★★★★
It sure is a game with an unique level of quality. This game has even more customizations, story and scene variations than the others Miconisomi's games. I would give it a 10/10 and you all should try it, unless you…
Red-pinky2026-02-13★★★★★
"One of the best 3D games out there! Great story, beautiful environments, and extensive character customization. The game runs smoothly and features a perfect UI/UX . There's still so much room for development—highly recommended!"
Breeze30052026-01-31★★★★★
One of the best animation games ever. Needs a lot of add-ons and customization though. And gangbangs and other positions. I think that is only fair for a game that has reached quite an audience. I hope the developers can…
★★★★★(18)
