Disproportionate Retribution: Monitor asked Nedzu what the punishment for being late to a meeting is and asks if electrocution can be used. Keep in mind that they are asking this because Izuku was "late" for a meeting he was not offered to attend with no given time. When Izuku interrupts, Monitor takes this as more reason to punish him.
Izuku is introduced to Hatsume Mei by proxy of her robot. The machine — Designation 17 "Sonic Spider" — crash-lands right outside of Izuku's school and commits "testing" (attacking him unprovoked) before self-destructing, the only thing left being a cylinder that ives him her business card and a message congratulating him for "[catching] the attention of the greatest inventor known to man!" Later, she doesn't even recognize him when he confronts her in person.
Monitor is introduced threatening to electrocute Izuku for being late to a meeting with Hatsume (a meeting that Izuku was never invited to with no set time) and then threatens him more when they and Nedzu get lost in a conversation that Izuku then interrupts.
"The Reason You Suck" Speech: After meeting Mei, Izuku gives a scathing one to both her and Nedzu for making the bullseye on his back exponentially bigger, putting his mother and Eri in more danger.
