>>101188496Muscle, at first, thinks that if Muscle does a good job raising children, Bendy will make it so Muscle can also be a Hero.
Muscle does everything he can to support Bendy, despite it being selfish reasons. While it started as selfish, Muscle eventually realizes he has been a terrible parent figure and even admits this to Shield while at weakest moment.
Muscle, finally admitting Muscle needs help, receives some! First, Baby is taken in by the aunt to let Muscle Sleep. Shield who now sees Muscle needs help even helps clean and takes care of Dash.
Meanwhile Bendy, despite being spoon fed a mission, eventually realizes the truth all on her own. Sadly it is too late, but this is basically the same as when Muscle was betrayed the first movie. When Bendy is in trouble, just like the last movie the domestic partner rushes to aide of their loved one to help them. Children also show up to help and their help, like the last movie, is the difference between success and defeat.
In the end, Muscle listens to the others instead of barking orders. Muscle takes the support job of stopping the boat. Bendy captures the super villain. The day is saved.