yaranaika? やらないか？

In Japanese, yaranaika? やらないか？ means "won't [you] have sex with [me]?" The meme comes from a gay pornographic manga of the bara バラ genre.

Literally, it means "won't [you] do [it]?" It's the verb yaru やる, "to do," plus the negative -nai ～ない suffix, plus the doubtful ka か particle. However, yaru has various secondary meanings, like "to give," and, used as a slang, "to kill," and "to have sex with."

Adult Manga: Kuso Miso Technique くそみそテクニック

• sou omotteiru to
  totsuzen sono otoko wa
  {boku no miteiru} me no mae de
  tsunagi no hokku wo
  hazushi-hajimeta no da...!
  そう思っていると突然その男は僕の見ている目の前でツナギのホックをはずしはじめたのだ・・・！
  While [I] was thinking like that, that man, in front of [my] eyes [while] {I was seeing [him]}, started undoing the hook of [his] jumpsuit.
• yaranaika
  やらないか
  Won't [you] do [it]?