I actually had that thought too... Like Jingi defaults to fingers in the mouth as a violent form of kissing that was done to him when he was a kid and he does this multiple times with Myeongil (like that one chapter where Myeongil bites his thumb and later you see him kiss the bite mark). It's only now that Myeongil is reclaiming the meaning and showing him it can also be a form of intimacy by willingly sucking on his fingers.
Godddddd they've really done EVERYTHING but kiss lol

It's basically an entire chapter of Jingi/Myeongil foreplay (≧∀≦)
1) Jingi going to town with nipple play/sucking Myeongil off/fingering him. Myeongil gets frustrated by how gentle/slow he's going lol
2) Jingi has Myeongil suck on his fingers and tells him it's like 'kissing multiple people'
3) Then Myeongil goes in for a real kiss, but Jingi still won't let him. Dude is this what edging feels like? Cmonnnmm! Although Myeongil does put Jingi's fingers back in his mouth to show he REALLY wants that kiss which I think broke Jingi
4) chapter ends with Jingi finally having his dick out and Myeongil pushing him down and climbing on top of him
Man I think this probably my favorite Jingi/Myeongil chapter so far. Just a little foreplay got me on my kneeeees