Gonna put out a wild random guess now: Iruma finds the legendary beast, but would have to kill it in order to win and instead saves it. Tournament ends, Iruma loses, possibly with 0 points. Iruma COULD have easily won, but Iruma being who he is refuses to win on principal.
It's a 'legendary leaf' (I said marijuana in an earlier chapter lol), implying it's a plant and not a monster although the two are not entirely exclusive. I actually like that though, I think a situation where he clearly could have won but chooses not to for some reason could be a pretty decent ending. He's always standing out for random reasons too, so it fits his 'curse' if he gets even more famous because rather than being the winner, he found the special thing but let go of it for some noble reason. Which the papers would latch on to.
I am most impressed by ice girl, she has some impressive creatures as summons, and her control over them and the rest of the animals is really impressive.
Bachiko was shy at first but then General Furfur said to just withdraw then Bachiko raised her voice against him because she knows Iruma can do it, not to mention he's the only student to stay till the end of her training