Crossdressing Protagonist as a Secret — The protagonist (male or female) of that game is crossdressing and has to keep their crossdressing under wraps, otherwise there will be consequences. The most common example is when the protagonist has to infiltrate an all-girl school and for that is forced to crossdress. Another example would be when the protagonist likes to crossdress but doesn't want people to know, because they will be.
Crossover — This story features a crossover. A fictional crossover is the placement of two or more otherwise discrete fictional characters, settings, or universes into the context of a single story. They can arise from legal agreements between the relevant copyright holders, unauthorized efforts by fans, or even amid common corporate ownership.
Crotch Rope Walk — Scenes involving crotch rope walk take place during the course of this story. Crotch rope walk is a BDSM practice in which a length of rope is pulled relatively tight and fastened across the room at waist height. Then the (usually female) submissive is to put the rope in between her legs and to start walking slowly. The rope bites into her private parts, causing pain and/or pleasure, depending.
Cum Bath — This category involves the full or partial submerging of characters in a semen filled container such as a pool or bathtub. This may be due to a bukkake. NSFW Example NSFW Example 2