Ero ★ Lab ~Jikken Suru to Doushitemo Eroi Kekka ni Shika Naranai Kenkyuubu~

The heroine and the protagonist live at a school famous for specializing in research.
Due to a number of failed experiments and accidents, their bodies somehow end up overlapping!? Their feelings deepen as they repeat foolish experiments and have sex in various situations.

Eventually, there is no need for the two to have any incidents--
this is a love story where the heroine enjoys the strange fate of her life until her secret desire comes true.

[Translated from Getchu]