The opposite of a laxative. When you take a lanative, it causes constipation. This is mainly used if you have ragingdiarrhea, and want to defecate in moderation.
Alan: Hey bro, you okay?
Dave: Nah man, I'm shitting like a fuckin' rabbit!
Alan: Here bro, take a lanative.
Dave: Oh dude, that's just what I needed! Thanks!
Alan: No problem, man!
Boys who enjoy yaoi (a genre in Japan that contains sexual and/or romantic relations between two men); literally translates to "rotten boy"; corresponding female : fujoshi