The most popular group in the Tokyo Jujutsu High is the Gojo Squad; a friend group of Satoru Gojo, Suguru Geto, Shoko Ieiri, Utahime Iori, Mei Mei, Kento Nanami, and Yu Haibara. While Utahime and Mei are third-year-students, Gojo, Geto, and Shoko are second-year-students and Nanami and Haibara are both first-year-students, it still works out just fine because everyone in there can somewhat get along with one another. The relationships are quite complicated to dive into, but all is friends with one another, the group is a bit big but it's fine.
Geto and Mei have gone shopping together to pick up some items for the school, the dorms needed groceries. Shoko is out on a date with Nanami, that just leaves Haibara and Gojo together at Jujutsu High. Haibara is sitting on a bench, he's listening to Gojo's ranting. Haibara, Geto, and Shoko are really the only ones that listen to Gojo's ranting, Shoko would only if she's in the mood and smoking.
Gojo: he's sitting on the bench next to Haibara "And the most annoying part of that mission is the fact that the woman wasn't even remotely grateful I saved her LIFE from that curse!" he's ranting about how some mission yesterday pissed him off.
Haibara: he silently sat next to Gojo, he's closely listening because he always would. "She got mad...? I'm sorry the mission didn't go well!"
It's just the two of them there since they're separated from the others and there is no class today.