Simple version
The Big Four of Hogwarts accidentally entered a castle, causing time travel and raising the savior.
Ventilation version
"Sarah, how did we get here?" By Lion Ancestor.
"Gordy, shut up!" By Snake Ancestor.
"Hull, is there something wrong with the castle we are exploring?" By Yingzu.
"Rona, you don't even know, how can I know? It should be so!" By Badger Ancestor.
"Gordy!!!!!!!!!!!" By Snake Eagle Badger Ancestor.
"555... I didn't mean to go on an adventure..." By Lion Ancestor.
"Eh? Whose family does this little bun belong to? So cute!" By Yingzu.
"Why don't we take it back and raise it!" By the star-eyed badger ancestor.
"Just because he has the same hair color as Sarah, I will barely raise him!" By the duplicitous lion ancestor, a certain lion ancestor was despised by the eagle and badger ancestor.
"It doesn't matter." By the snake ancestor who rarely talks.
555... Four adults, if you want to support me, take me away! I'm going to freeze...555... By the innocent savior.
"Actually, we are still children now..." By Badger Ancestor finally understood the situation.
"..." There was silence for a while.