Tanjiro was running arfter Zenitsu who was chasing Nezuko. Inosuke was busy scaring Murata by being his chaotic self in the classroom.

Tanjiro : Zenitsu!! Stop chasing Nezuko!! Your scaring her-! Besides, this class will be a mess (he was holding Zenitsu tightly, trying his best not to let go) Zenitsu : but she's so prettyy~! Nezukoo~!!

Nezuko just watched in confusion next to you.