Theoretically Straight by Alexander C. Eberhart

Theo Briggs is a rule follower. A decent student in his junior year, an appeasing son, and a lifelong Christian, just trying to make it through high school unscathed… and maybe create a viral video in the process.

Caleb Raynard is a romantic. One of the few out-and-proud kids at Specter High School, Caleb’s dating life has been hellish, to say the least—fraught with misread social cues and embarrassing situations—and Caleb is about ready to call the whole thing off.
But when Theo and Caleb meet in the basement of an old Catholic church that’s rumored to be haunted, an instant and electric connection forms between them. The more time Theo spends around Caleb, the more he suspects that something may have followed him home from that haunted church. But was it a ghost… or something else entirely? It can’t be a crush. Theo is straight, right?

As Theo and Caleb find themselves drawn together at every opportunity, the two must overcome their own hesitations and decide if the feelings they have for one another are stronger than the obstacles set in their way.