Soosh Bro" (alternate spelling "Sush Bro") is a terrible phrase coined by Bros who like Sushi. Bros, according to Merriam Webster's online dictionary, are wont to shorten common phrases and create new inside jokes that make sense to no one. What kind of assholes do that? The Inner Circle has adopted this phrase in a reverse meta hipster way. It is said ironically, and yet it seems to creep into normal conversation with total acceptance.
One day, Jojo went to a Sushi restaurant with his girlfriend Julie (It's one of Jojo's favourite stories, and he even told it to Julie, but she has to remind him that she was there). While standing in line, some Bros entered the restaurant and stood behind him. One Bro said to the other Bro "Let's get some Soosh Bro!" and the rest is history.