(This comment is just a joke) What if this is the way all of the girls where foing to die if Rentaro didn't start dating them?
Shizuka kidnapped and married to a bad guy
Kurumi making someone angry and then that person would kill her
Kusuri eaten by a wild animal while trying to use them to experiment her drugs (or she turned someone into a a animal)
Hahari killed by someone with an axe after trusting blindly into that someone
Iku dying from body exhaustion
Naddy family forcing her back to how she was before
Momi going to prison for sexual harassment
Meido (somehow) managed to get the zigs with rentaro, but never saw him again
Yaku's family got exposed for their bizarre drugs and then got killed or slaved by a gang or the government
Meme got so embarassed someday she secluded herself
Mimi died poisoned
Chiyo died homeless in the cold
Hakari OD'd herself accidentaly
Yamame went into a coma
Nano isolated herself from society
Karane is the only one i couldn't think of something.
(This took more time than i thought)