Young girls sucking to please guys and keep them around. Nipples are successful and attract males. Everyone wants not only to fuck her pussy, but to give her in the mouth and cum after that. It's a pleasant sight - the partner's lips smeared with cum, the drops dripping from the end on her tongue, her breasts smelling of sex. For a man, this picture is the height of bliss. With that, the girl is down, expressing submission and acknowledging his power over her.
A little humor in porn is only a plus.
This guy who is tied up, he appears in many videos, I think, as this simpleton who gets cheated on by his girlfriend. Just look at his face, it simultaneously expresses frustration, helplessness and cowardice. I wouldn't be surprised if, after the lover left and the girl untied him, she only had to say a few sweet-faced phrases for this cuckold to forgive her.