In Japanese, the island of Erromango is "Eromangatou" (エロマンガ島), or "Eromanga Island." The words "ero" (エロ) and "manga" (マンガ) are clearly visible, while the kanji 島 (shima or tou) means "island".

This is why one man, it seems, decided to visit and bring ero-manga themed comics to show the locals.