BL Elektel Delusion

Fan made

Continuation of Maru & Mu's story in "Elektel Delusion"

Shunpei and Fumi are best friends and neighbours. One day, Fumi tells Shunpei he might be gay and has agreed to go out with another guy in school. Shocked at this sudden confession (but very accepting), Shunpei questions Fumi about all sorts of things regarding his newly-discovered homosexuality - subtly aware that he's disappointed that Fumi picked someone else over him - and, upon meeting the boyfriend, cannot take that Fumi chose someone who was more or less normal... like Shunpei!
NOTE: Chap

From Vices and Devices:
Yumeji has a big problem, and no, it's not that he's gay (for now, anyway). Despite his good looks, excellent grades, and talent for sports, he's not getting any, and it has everything to do with the fact that he's impotent thanks

Mu's in love with his best friend Maru, but Maru doesn't take him seriously because, well, Mu's a huge slut who will sleep with anything that moves. So Maru suggests an "endurance contest": he'll sleep with Mu if Mu can hold out for ten days without sex.

Included in "Otona Keikenchi" (ch3)