Go-toubun no Hanayome ∬ ~Natsu no Omoide mo Go-toubun~
五等分の花嫁∬　～夏の思い出も五等分～
This is a PC conversion of The Quintessential Quintuplets visual novel (https://vndb.org/v29889)
Runs on the PC version of the engine of the original version.
It is possible to play with a keyboard but no mouse support is present.
For keyboard the mapping is

Arrows = Arrows
Z = Cross
X = Circle
C = Square
V = Triangle
LCtrl, RCtrl, PgUp = R1

Other keys don’t seem to be mapped, but you can use a controller or a controller emulator to get around that (though the keys that are mapped should be enough).
You can also set the window size and full screen mode in the 5toubun.txt file in the game folder (should be pretty self-explanatory, just don’t change SCREEN_W and SCREEN_H values, use WINDOW_W and WINDOW_H instead).

JAPANESE LOCALE REQUIRED
(alternatively, remove ∬ character from the game folder name and it should work on any locale, though not fully tested)