he practically traumatised him, he made him think that he made out with a dog (when he had a rut he lost his memories) when he actually slept with his now partner Joshua, that’s why Chase had developed a trauma with dogs, and then he took advantage of it, also their pheromones attract other people and he forced him to go to these pheromones parties even though he didn’t want to. Also being the only brother who is not “crazy” who actually has emotions, Grayson used this against him basically
So as you can see Grayson's f up in the head, that's due to him being a dominant alpha who are all pretty detached from feelings and all that stuff. Grayson himself has trouble understanding any of his own emotions, but his father who's also nearly emotionless (due to a lot of different reason like his parents who had the most toxic and tragic story in the "If you Can" verse) fell in love wich is why he wants to fall in love to feel smt.
As u read, you see that Dominant alphas need to release their pheromones frequently or it can have direct consequences like brain damage or death, but Chase, unlike the rest of his siblings who are all psychopathic can feel empathy and a bunch of other stuff despite being dominant. And bcs of his own beliefs he can't handle sleeping around bcs he's a dominant alpha, but as I've said before not releasing ur pheromones when u're dominant=death or brain damage, so Chase uses medication wich has very bad side effects. As time goes on his body develops resistances making him take stronger medication wich might also greatly damage his health and body (what happened to their father actually).
So Grayson was pressuring him to go to pheromone parties, but Chase refused to sleep w anyone, so one day when Chase was going through his rut, at the end of it, Grayson came into his room w his dog Alex i think? And let Chase assume he had slept w the dog (Chase was feeling refreshed after his rut when he usually feels like shit wich meant his instincts got satisfied).
Thinking that this would push Chase to finally start sleeping around and release his pheromones (Grayson thought he was helping him, and i'm srs he genuinely believes that), but as a result Chase went into a panic attack and shot the dog to death.
Then he developed PTSD so bad that even seeing dogs leads him to have a panic attack and to freeze up (the thing is that during his rut he had slept w an actual person wich is Joshua Bailey an omega who was working as his bodyguard and who got pregnant as a result had a son and all that without Chase knowing, until Josh got hired again as a bodyguard for him and having the whole "Kiss me If You Can" story)
Joshua is that character that was looking at Dane while speaking on the phone w him and "Desire me if you Can" is a bit after the end of "Kiss me If You Can" (Tbh Chase and Josh's story is prolly the healthiest out of all of ZIG's stories and it's rlly funny how Chase puts the dumb in dumb blonde).
If you're interested in the other members of the family their stories weren't adapted yet (their darkest stories are Grayson's grandparents like I first mentioned wich was toxic on both ends and horrifying too).
Then u have Grayson's eldest brother Nathaniel and his partner Chrissy who both work as a Prosecutor and Lawyer, but committed the most crimes smh, they're both toxic in an attempted murder way??? But apparently it's pretty good and has a happy ending.

sooo i havent read other works in this series because idk i just cant get into them but this one hooked me immediately. can someone tell me what exactly did grayson do to his brother, chase?