Masaki Michishita, a "typical guy" enrolled in preparatory school, is running to the park washroom when he spots a man wearing a jumpsuit sitting on a nearby bench. The man, Takakazu Abe, then unzips his jumpsuit and exposes his penis, asking Masaki, "wanna do it" (やらないか, yaranaika?). They then proceed to the washroom and have sex.
(Source: Wikipedia)
Note: Published in BaraComi 1987 #2
