Ano Ko wa Toshi Densetsu.

Spreading among lolicons is an urban legend about Zangyaku-san, their greatest enemy, akin to a death god. Armed with a cockroach repellent, one must never take out their dick in front of the mysterious young girl, lest they never wake up again. Other that that, little is known about her, and so the best account is a certain lolicon's letter, addressed to his parents. Priding himself in being a natural lolicon, one who has always been and always will be like that, and in adhering to the way of the lolican, he resigned himself to a lonely and dull future. Unfortunately, he encountered Zangyaku-san. Twice. Injured yet alive after each time, he resolved to be more careful after the first. However, being insulted as 'fake lolicon' at their second meeting made him throw all caution to the wind. Taking the name Rapeman and donning a paper bag, he sets out to take revenge on the elusive legend.