Narcisistic guy who pretends he’s good in front of other ppl?

Just gonna follow the question

False memories
Black mirror

Same

No love zone

BJ ALEX (totally what u r asking for )
paid fujouking
At the end of the road

Peach love (dude was hiding a huge secret)

All of these are coloured mangas with good art
A few of em might have the guy being different in front of ppl but completely different in reality

http://www.mangago.me/read-manga/semantic_error/
Currently reading this , it’s a coloured shounen ai manga
The guy seems to match your description so I’m just gonnna leave this here