Support the original artist, Tira: https://www.pixiv.net/en/users/663188
Translated by lan03: https://www.pixiv.net/en/users/43668569
Original Work:
https://www.pixiv.net/user/663188/series/75936

This translation needs a LOT of work. I have absolutely no idea what is going on.

Base +8, mar-bcrle +6

@Kerokami
As far as I can tell. Girl is bisexual and while the girl she's sleeping with know's she has a boyfriend he doesn't know she has a girlfriend. Girlfriend then say's she wants to experience sex as a guy and the boyfriend is lured to a private area where their heads get swapped. They then proceed to have sex with "her" before deciding they prefer sex with a male but like their own personalities meanwhile the boyfriend has masturbated as a girl and prefers that. So they swap him and the girlfriend back and then him and his girlffriend because her more boyish build is easier to hide. At the end they appear to be discussing if they'll have the boyfriend in the original girlfriends body get pregnant or be reminded she needs birth control now. Essentially

Bisexual girl in relationships with boy and girl.
Swaps boyfriend and girlfriend and has sex with her while leaving the boyfreind to masturbate in said girlfriends body.
She and the girlfriend decide they prefer their relationship but want a male body to swap around between them.
Girls decide she prefers the girlfriends relationship but wants a male body.
As the girlfriend is too obvious (large breasts) to leave swapped they swap the boyfriend and original more tomboyish girls body gaining his agreement as masturbation as a girl was more pleasurable for him.
Boyfriend is left trying to hide she's a girl (be interesting to see her reaction to her first period) and the girls presumably keep dating and swapping the male body around while also having sex with the boyfriend who they appear to be undecided if they want to get pregnant or not.

Base +6