A look at the relationship between Mike and Sulley during their days at Monsters University -- when they weren't necessarily the best of friends.

Johnny: Enjoy the attention while it lasts, boys. After you lose, no one will remember you.
Mike Wazowski: Maybe. But when you lose, no one will let you forget it.
Chet: Oh, boy. That is a good point.
[as the Oozmas are watching the Scare Floor at Monsters Inc. in order for Mike to show them what it takes to be Scarers, they soon get caught by the Security Guards with their flashlights]
Security Guard: Hey, what are you doing up there?
Art: [Panicking] I can't go back to jail!
Sulley: I act scary, Mike. But most of the time, I'm terrified.
Mike Wazowski: How come you never told me that before?
Sulley: Because we weren't friends before.
Young Mike: I found a nickel! Sure wish I had pockets.
Sulley: Were you kissing my hand?
Mike Wazowski: [laughs] No! And what about you with all your shedding?
Sulley: I don't shed.
Mike Wazowski: Really?
[punches the mattress of the top bunk and Sulley's hair falls everywhere]
Mike Wazowski: Um, h... hello? Fella
[as he and Sully walk down the basement into a candlelit are, where O.K fraternity surround it, wearing black clocks]
Don: Do you, pledge your souls to the Oozma Kappa brotherhood.
Mike Wazowski: [Terri and Terry hit Mike with a cricket bat] OW!
Terry: Do you swear to keep secret.
Terri: All that you learn
Art: No matter, how horrifying.
Sulley: [Squishy hit Sulley with cricket bat] Hey!
Squishy: Will take the scared oath of the...
[initiation interrupted by someone, turning on the lights]
Don: For crying out loud.
Ms. Squibbles: Sweetie, turn the lights on when your down here. You're going ruin your eyes.
Squishy: MOM, WE'RE DOING AN INITIATION!
Ms. Squibbles: Oh Scary, well go on. Just pretend that I'm not here
[turns off half the lights, and walk downstairs to the washing machine]
Squishy: This is my mom's house. Do you promise to look out for your brothers?
[Mrs. Squibbles turns on the laundry dial loudly]
Squishy: No what the peril?
[Laundry machine runs noisily]
Squishy: ... WILL YOU DEFEND OOZMA KAPPA? NO MATTER HOW DANGEROUS?NO MATTER HOW INSURMOUNTABLE? THE ODDS MAYBE? FROM EVILS BOTH GREAT AND SMALL? IN THE FACE OF UNENDING PAIN AND... OH FORGET IT. You're in.
Slug: I can't be late on the first day!
[Starts huffing and puffing as he crawls at a slow rate]
Dean Hardscrabble: It's my job to make great students greater, not make mediocre students less mediocre.
[Mike and Sulley are working in the mail room at Monsters Inc]
Yeti: Alright, newbies. Quit goofing around. I'll have you know that tampering with the mail is punishable by banishment.
Sulley: Yes Sir.
Mike Wazowski: We're right on it Mr. Snowman.
[Mike and Sulley are being escorted out of the door lab by the CDA after causing the door to explode with the big scare]
Squishy: What's gonna happen to them?
Roz: That's for the university professor to decide, but I can assure you we'll always be watching these two. Always watching.
Mike Wazowski: Squishy. We're not gonna lose, because we have everything we need to win right here.
[points to his chest]
Squishy: [smiling] Heart.
Mike Wazowski: No, me! I'm gonna win the race for us.
Sulley: [to Mike] You're not scary. Not even a little bit. But you are fearless, and if Dean Hardscrabble can't see that, then she can just...
Dean Hardscrabble: [Interrupting] I can just... what? Careful, Mister Sullivan, I was just starting to warm up to you.
Sulley: ...sorry.
Sulley: You don't need to study scaring, you just do it.
Greek Council VP: Trust me when I say you are not gonna want to touch this bad boy!
Art: I wanna touch it!
Don: Want to join Oozma Kappa?
Squishy: We've got cake!
Don: Sherri and I are engaged.
Mike Wazowski: Who's Sherri?
Squishy: [Embarrased] She's my Mom.
Don: Don't worry Scott. I don't want you to think of me as your new dad. After all, we're fraternity brothers first.
Squishy: This is so weird.
Don: Just think of me as your big brother that's marrying your mother. Wait, hold on, we're brothers who share the same mom slash wife.
Dean Hardscrabble: You did what?
Sulley: My team had nothing to do with it. It was all me. I cheated.
Dean Hardscrabble: I expect you off campus by tomorrow.
Sulley: [in dismay] Yes ma'am.
Dean Hardscrabble: You're a disgrace to this university... and your family name.
Dean Hardscrabble: You two have managed to accomplish something together no one ever has: you surprised me.
Mike Wazowski: I've been waiting for this my whole life! I'm gonna be a scarer!
Sulley: [Introducing himself] James P. Sullivan.
Mike Wazowski: Mike Wazowski.
Sulley: [On the Day of the Final Exam] I'm gonna wipe the floor with that little know-it-all.
Johnny: Yes you are.
[Takes Sulley's ROR Jacket]
Mike Wazowski: My chances are just as good as yours
Sulley: You're not even in the same league with me.
Mike Wazowski: Just wait, hotshot. I'm gonna scare circles around you this year.
[after being humiliated from Sulley's performance during the Final Challenge in the Scare Games]
Randy: That's the last time I lose to you, Sullivan!
Professor Knight: Show me some slobber! Drool is a tool, kids. Use it!
Dean Hardscrabble: Mr. Wazowski, what you lack simply cannot be taught. You're just not scary.
[as Sully and Mikey leave]
Dean Hardscrabble: Good luck.
[Frank McCay, right after doing his scare on the Scare Floor, is surprised to see Mike right behind him]
Frank McCay: That was real dangerous kid! I didn't even know you were in there. Good job!
[Gives Mike his MU Cap]
Mrs. Graves: What have you to say for yourself?
Young Mike: How do I become a Scarer?
[Mike notices that his settings on the Scare Simulator had been set to the Lowest Difficult instead of the Highest like the others, which is how he broke the record in the Final Challenge of the Scare Games, beating the RORs]
Sulley: C'mon Mike, I don't think you should be messing with that. Mike?
Mike Wazowski: Did you do this?
Sulley: Look Mike...
Mike Wazowski: Did *you* do this?
Sulley: [sighs] Yes I did.
Mike Wazowski: But why?
Sulley: It was, well, you know, incase we lost.
Mike Wazowski: [Feeling upset] You don't think I'm scary! I thought you believed in me. But you're just like Hardscrabble, and everyone else!
Sulley: I was just trying to help!
Sulley: I didn't need your help! I'm way scarier than you! I'm scarier than any of you!
Sulley: Well what else was I supposed to do? Let the whole team down because you don't have it!
[Offended by that, Mike storms off, and Sulley begins to feel sorry for himself]
Sulley: Mike wait!
[the rest of their team standing nearby heard everything, and Squishy sadly drops their Scare Games trophy to the ground]
Sulley: We need to find a New Team.
Mike Wazowski: We can't just get a new team! I checked this morning, it's against the rules.
[after Dean Hardscrabble tells Mike that his team is short one person to compete in The Scare Games]
Mike Wazowski: But, you need six guys right?
Greek Council VP: We count Bodies, not Heads.
[Pointing at Terri & Terry]
Greek Council VP: That Dude counts as One.