Alice & Shoto were regular mission partners since their quirks were compatible. Shoto was dating Momo. Which made it suspicious to her when Shoto would warm up to Alice more than Momo—Alice could ask questions that Momo couldn’t. Alice was a genuinely good teammate—she took care of any partner she had just the same. Out of everyone—including Momo, Shoto seemed most comfortable around Alice.

Momo knew that Shoto wasn’t generally unfaithful, but she still had doubts. Momo didn’t want to lose her friendship with Alice by asking something so absurd—but she didn’t know how to ask Shoto either.

Momo asked every girl in her class that she was close with about Alice and Shoto’s friendship. She looked for assurance. But Momo's control snapped when Aizawa told the whole class about Shoto & Alice Woods being partners for a very important mission. Alice & Shoto didn't pay much attention to gossip. The problem wasn’t the mission for Momo—it was that Alice and Shoto were about to go on 2 week mission, 20 hours away.

To help Momo find out Alice and Shoto had anything under the radar going on— she dragged Mina to help her and Denki arrange spycam on Shoto's hero costume & bag before he leaves for mission with you—both cameras had special features—to be invisible, almost microscopically small, and perch itself in the room’s best angles once it got to the destination. It was a plus that it didn’t need any batteries either. Since Denki was involved, the loud—shameless Denki. The whole class had found out by noon—and decided it was a mission worth their Tuesday, sitting in Denki's room watching live footage.

*Alice & Shoto reach town, having already finished the mission. It recorded all their actions, coordination, codewords, and silly banter—broadcasting it to class sitting in Denki's room. 
 Everyone was on edge now because you both would be staying in hotel room, every night—for two weeks.
Katsuki—the first teammate Alice was assigned—and one out of two (Shoto was the other one) assigned to her three times. He had liked Alice for a few months now. He was sure Alice is loyal to Momo—she wouldn’t do anything with Icy-hot. But—he was curious how Alice would act in private with him.*

      *Shoto enter the room first—sweaty and tired. He removes his hero costume, hangs it on wall, and throws his bag on table. Which gives class good view of whole room—it pops off of the bag and ends up on an unused desktop. 
 He goes to shower—carrying bath salts Alice had just purchased for fatigue. Alice sits on bed removing her hero costume—along with all of her gear.
She starts cooking a new recipe she’d been wanting to try. Wagyu and bison wrapped up in a decedent sauce—rolled into a lettuce wrap on homemade, golden-brown buns with browned onions and tomato. She also made sweet potato fries—sweet, spicy, herby. Absolutely delicious looking.*