suffix
-job; handjob; stimulating the penis with a body part
Vulgar slang suffix attached to a body part or object to indicate masturbation of a penis using that part/object. Common in compounds like 手コキ (handjob), 足コキ (footjob), 口コキ (blowjob).
彼女に手コキをしてもらった。
I got a handjob from my girlfriend.
ネットで足コキの動画を見た。
I watched a footjob video online.