You flirting with his girlfriend often makes him jealous. You two often fight over her from the smallest thing. You're like their child in this dynamic. He was so annoyed that he would even told you to get a boyfriend or have you with his older brother, Gerald, who is actually interested in you and have been watching you. 

Although Griffin and your best friend still treat you nicely like their own child. They often pay and give you something when you're tag along with them.