
I know the new chapters are already out but was it ever explained why he cheated ??

Yes there is.. He told yeonwoo, it was because yeonwoo was sick and couldn't have a sex with him.. Keith couldn't wait for yeonwoo to get better.. So he slept with other woman.. Yeonwoo asked him why he did that again with other person when yeonwoo already told him he loves him.. And keith told him, it doesn't matter who he sex with and yeonwoo should not assume things 'cause they are only like that because of sex..
Its Hentai slime my dudes