It's small but, when Presley and Nefer-Tina revealed to the others that Rapses was in on her secret identity as a girl back in ancient egypt and kept it.
The Episode "Eye of the Beholder" had a nice little moment near the end. Chontra captures Presley, Rath readies to battle it out in a duel with her. Chontra mocks him for caring so much for a pupil, Rath then openly admits that he cares for Presley as if he was his own son. Considering this is Rath we're talking about, that's saying something.
Later Presley tells Rath not to feel bad about his lost love.
Presley: Don't worry, Rath. Everybody's been though one of those bad break-ups.
I liked the focus on Rath in "Dead Man Walking", when Rath smashes into a wall and loses his memory. All the time he spent with those homeless people was nice to watch (even if Rath was still, well Rath). When he tries to help them despite his amnesia and gets hurt, his new friend Rosey really puts his true nature into perspective.
Rosey: Kind, patient, understanding.
It's true Rath isn't perfect but, he is a pretty cool guy.
During much of "My Dad the Hero" Jakal is suspicious of Presley's father Paul, who's come for a visit. Paul takes Presley to the carnival and the pair have a great time. Only problem is that Jakal is suspicious and catches the man cheating and lying to Presley about it. When Jakal finally does confront Paul (after saving him and Presley from Scarab, who Paul admits he was going to give a stolen antique in exchange for cash) it's obvious that he doesn't approve of the man. But once Paul's helped the Mummies defeat Scarab, Jakal and Paul reach an understanding and part on good terms.
In episode 14, Scarab casts a spell pulling Rapses into the present, meaning that Presley is no longer the incarnation of Rapses, and the mummies are no longer obligated to look after him. Unsurprisingly, Presley feels neglected as the mummies focus all their attention on Rapses, and even begrudges Rapses for this. However, in the battle at the end, Jakal protects Presley as well as Rapses, because he's still Presley's friend, even if not his Guardian. Rath echoes this sentiment after Rapses returns to his proper time.
Jakal: "Even if I'm not your Guardian, I'm still your friend."
Rath: "You are Rapses again. Our Prince and our friend."