beta
against abe no seime ("ans"). ans might have the divine power of clairvoyance, considering haruaki's connection of "clairvoyance" to his memories of ans being able to see haruaki even in memories, etc.
i believe he may have "seen" or "had a feeling" that douman (principal) was going to become the principal of a youkai school. ans' goal to "spread knowledge" to youkai & all, which he had shared with douman, if he really was a clairvoyant & could see his future-self, he would have seen himself capable of doing so in his reincarnation as haruaki. in connection to that, an alternative theory is that he simply saw himself as haruaki, & even if he didn't know douman would eventually become the principal of the school itself, he believed he, as haruaki, would become a youkais teacher nonetheless
so, to me, douman feels more like a "tool" to ans accomplishing his wish. while he did "win" against ans because he was the first to build a school & spread knowledge to youkai, i personally wouldn't say he "fully" won against ans in this small aspect, lol
it would be funny if he found out. considering this is a gag comic, he might j throttle haruaki's soul out of him to beat up ans himself, ditch him in the sea & then pull him up & put him back in haruaki & j say "oops, your soul tripped & fell <3"