Technically not, but Mt. Lady does sort of flirt with Todoroki at one point and calls him "just my type." The teacher Midnight could also be seen as uncomfortable
There's also Twice sometimes flirting with Toga, even calling her "my wifey"
what immediately comes to mind is somewhere near the end of season 2, when a character with a quirk to speak to animals commands bugs to attack/distract a teacher. its not too important to watch the whole thing and can be skipped
Minors are regularly shown in suggestive situations throughout the show, mostly the female characters. Yaoyoruzu, for example, is frequently hit on and her hero costume leave most of her chest exposed (she also has a few scenes where she's mostly topless, or fully but it is censored.) Toga is also sexualised, and the character of Mineta regularly sexualises and tries to grope and spy on the girls in the class.
Bakugou vomits after getting punched in the stomach Shigaraki pukes a lot in season 5. Uraraka sometimes pukes after using her quirk, but her puke is rainbow and sparkly. The gagging just sounds like her sticking her tounge out like she's at the doctor lmao
Bakugou tells Deku to "Take a swan dive off the roof of the building" And later Deku is thinking "telling someone to kill theirselves...what if I actually did it?"
Female characters on the show are frequently sexualised, and the minor characters in the series are no exception. The main class is 15-16, and frequently they are seen in situations where that are suggestive. Adult characters also are sexualised.
Season 5 Episode 23
Tomura Shigaraki activates his quirck (decay) in the origin story while hugging his dog.