Sexual assault of a child and violence toward children (discussed in dialogue): The human protagonist's sister was raped and beaten as a child. The perpetrator also cut the protagonist's face, leaving permanent scars.
Suicide (discussed in dialogue): The human protagonist's sister committed suicide as a result of her trauma.
Noncon: The alien protagonist's mating cycle causes him to go into a mating frenzy. At one point he aggressively orally stimulates the human protagonist without consent before he is able to get himself under control again.
Dubcon: The alien's body releases pheromones that act like the "sex pollen" trope, putting the main character into a heightened state of sexual arousal and even causing her to hallucinate a sexual encounter.