Class 1A comes to rescue Izuku after he was isekai’d, but they were very, very late

Whether it’s because of a villain with a inter-dimensional quirk, lab accident, or divine fuckery, Izuku becomes trapped in another world (fantasy for example) and tried to find a way back home before realizing and ultimately accepting that he can’t go back and locks in for the long haul.

Time goes by as Izuku becomes accustomed to this world and forges out a new life for himself. Until one day, when Aizawa and his classmates showed up to rescue him.

When they arrived to a house that the locals say once belonged to Izuku, they asked the owners if they had seen or heard of him, to which the family’s patriarch, a man named Toshinori, responded by inviting them all inside and into their backyard where an elderly man was watching over the children, and much to everybody’s shock, all of them had quirks and were spewing fire from their mouths and using telekinesis.

“Father, some people are here to see you,” Toshinori spoke, catching the old man’s attention. “They say they know you.”

The old man turned to face them and looked at the class with a shocked face before approaching them as tears welled up in his eyes.

“S-sensei? Guys? It’s really you!” The old man exclaimed as he embraced Aizawa in a sudden but unnaturally strong hug, revealing familiar looking scars on his arms that the students would recognize anywhere, alongside some new ones.

“…Midoriya/Deku?” Was all that the students could say before the old man, now revealed to be Izuku, broke down crying at seeing his friends again for the first time in years.

The reason for why he aged while everyone else stayed the same was that time worked differently in this world and the months that it took for them to get here ended up being years for Izuku (sixty, give or take).

So now class 1A is temporarily staying in Izuku’s family home and listening to him explaining everything that’s happened to him ever since he arrived.