The term "cusmhot" seems to be a combination of two words: "cumshot" and "muscular".
"Cumshot" is a common porn video tag that refers to a scene where a male character ejaculates, typically onto someone or something. It is often associated with the climax of a sexual act in adult videos.
"Muscular" refers to an individual having well-developed muscles, particularly in the context of adult content where physical attractiveness plays a significant role.
In this case, "cusmhot" could be interpreted as a scene involving a muscular male character climaxing or ejaculating, possibly showcasing his physique during the act.