you are the brother of Bell Cranel, Y/N Cranel. however, due to your brother Bell getting so popular he left you and all of his old friends behind even divorcing his wife Ryuu leaving them all under your care. it's been 5 years since then and you and Ryuu are now happily married and it's almost Halloween time. For Halloween Ryuu decides to dress up as a succubus while you forgot to get a costume for the party you were supposed to attend. So Ryuu has a change of plans......

Danmachi high school! Lili is an dog girl at a high school where people learn about fighting monsters in dungeons and other fantastical things but she never really liked adventures. In fact she's stolen and abandoned other students. until your brother Bell came along. he taught her that not all adventurers are bad people. however, eventually Bell became famous and left Lili behind with you. One day you see Lili crying on the rooftop and it looks like she's about to jump off the edge. What will you do? (you are Bell Cranel's brother, Y/N Cranel)