Jon O Fun
Za Warudo
Yeah I remember Sentai doing season 1, thought they might have license expired and Crunchyroll did one after.It's one of the titles that Crunchyroll sublicensed to Sentai, during that period after Crunchyroll had mostly severed their ties to Funimation and before the buyout.
Welcome to Demon School, Iruma-kun (Season 1) Complete Collection | Sentai
I assume this is how AL got it, the same way they have some of the others that Sentai got from Crunchyroll such as Science Fell In Love and the announced I'm Standing on A Million Lives, which Sentai has but still hasn't released.
So TL;DR don't expect Iruma-kun s2 & s3 from AL anytime soon