Some random portal or something is normally how any uncreative crossover would start. Kinda borrowing from this overused cliché has some losers, with dumb luck, start another world-saving adventure. It's within a magical school-type, furthering some other tropes. Kazuma and his underlings are prompt to an unwilling task after some freak accident causes another isekai.

Kazuma and Aqua make a deal with Whitley Schnee, in exchange for letting them have easy lives they would help him do all sorts of things

After the fallen of Beacon, team RWBY was separated. Everyone has paths they need to walk, but something is different. Ruby is acting strange after she wake up. Now she is always talking about magic and explosions.

Kazuma and Aqua become the new gods of the Rwby world

That unlucky man from R**nt's here, Kazuma! And he's way handsomer than I remember! Of course I'm leaving you, dumbass! I've been waiting for a moment this gIAH NO! WHY? WHY? YOU AND ERIS SHOULD GO DIE! [Sequel to "The World of Remnant According to Aqua and Eris"]

How weird would an explosion-obsessed huntress be? The answer is, very weird. But since when has that ever dissuaded Megumin, now in the body of one Ruby Rose, from showing the world how her magic — now semblance — is the best? [ONE-SHOT]

Once upon a time, two goddesses were assigned to be replacements for two dead gods who created and handled a world called Remnant. One goddess was their fangirl student, while the other was a wannabe. So now, Kazuma, you shall be knowing the true and real story behind how Eris trashed that world beyond repair! Hey, don't sleep on me, you idiot!

Jaune Arc finally did it! He defeated Cardin Winchester! So you better believe he celebrated in fact he died because of it! Fortunately for the Blonde Knight our lovable idiot goddess Aqua gave him a second chance in life so he can defeat the demon king...! As soon as Aqua stops crying that is

Hardcore Shut in Satou Kazuma died as he lived, like a loser. The Goddess Aqua had wanted to send him to Eris world, until another world required more urgent help. A world of fairy tales come to life, a world over ran by a great evil. An Evil that hes been tricked to fight if he want to live or at the very least survived.

Beacon Academy is a prestigious school that accepts all students of a certain caliber. Ruby Rose is a 15 year old who has been accepted alongside Weiss Schnee, Blake Belladonna and Yang Xiao-Long. They will form team RWBY. However, team KMAD formed by Kazuma, Megumin, Aqua and Darkness will spice things up. Join them on their hijinks in this wonderful world!