it's really great though i have a few criticisms. Particularly in the final parts.
1. Callum gets too much of the blame. I hate how one sided things are with Callum and it never feels like others get any criticism.
2. Marcus should've been called out more. He never tells Callum the truth about what happened and we the readers are supposed to feel sorry for him when he had plenty of chances to come clean. If i was Baxter and/or Troy I would be frustrated and tell him off because so much of the drama could've been potentially avoided had he been honest and allowed Callum to see Davids true colors. Callum isn't some lovelorn blinded fool, he's just someone who just thought he needed to help someone who didn't deserve. Not defending Callum but his actions are in a gray area because Marcus didn't come clean sooner
3. Some characters are wasted or pointless. Troy and Smoke are the biggest examples. Troy should've had a scene criticizing Marcus for not telling Callum the truth and be more supportive as a friend and Smoke should have more of a role in the final act as the secondary antagonist. Like what was the point of him? Especially with all the build up he does nothing substantial.
4. Rushed Reconciliation. I think there should've been more before Callum and Marcus reconcile. Have Marcus initially hesitate to forgive Callum so that Baxter can talk to him and get him realize he was in the wrong not being honest, and to stop feeling guilty about David. Have Marcus tell David off in a cathartic moment and then have a stand off ending with Smoke arrested and Callum telling David to go pound sand with Marcus, Troy, Baxter, and even Ronny and Adrian/Aiden having his back. Then end it with Marcus and Callum both apologizing for their mistakes, reconciling and making love with the two cuddling in bed for the night since their dads are gone til tomorrow, optimistic about their future now that David's gone.
Just my thoughts. Sorry if its long.