Isanghan Somunui Nyeoseokdeul!

NTR (Neighborhood Therapeutic Recreation), a volunteer club at Korea University's College of Physical Education. Though formed for service, rumors say it's full of weirdos...

Unaware of this reputation, our protagonist Kim I-Ban joined. He tried to leave, disgusted by the crazy members who claimed they could make Ban Seon-Woo, the club member with sexual numbness, only get aroused by nipples. But something's off... I'm not gay, and I don't want to get mixed up in weird stuff... I really don't... Why the hell is my usually quiet dick standing up?!

(Source: MrBlue, translated)

Note: Includes one extra chapter.