脇わきコキ

noun

armpit job; armpit sex

Slang term for a sexual act involving the armpit; vulgar and not used in polite conversation.

• ネットの掲けい示じ板ばんで「脇わきコキ」という言こと葉ばを見みかけた。

  I came across the word 'armpit job' on an internet forum.