The cigarettes, that is, not the characters.
As noted on GameOver, artist Shinrashinge uploaded photos of his "tobacco art", which is made from cigarette ash and tobacco leaves. He isn't a big smoker, writing, "I've kind of had a enough of cigarettes..."
Here's Sanji from One Piece, made from smoking two
Creating that character from smoked cigarettes makes sense! Ditto for Toushirou from Ginatama (below):
Not every character makes sense though.
I... didn't think Pikachu smoked. Maybe during breaks? After sex?!