Only if you didn't take 2 seconds to research the title.
Well, then everything is okay because I didn't,
Anyways, got some new info on Mikagura.
According to someone who knows someone who reads both the novel and the manga, there is a bit of ship teasing going on between Eruna and pretty much every character in existence, boy or girl. Eruna does show some interest in boys, but never more than anything platonic. In general, the series deals with every character's relation to every other character, not just Eruna x someone.
At one point in the novel she ponders about getting a love life but doesn't specify.
Her crush on Seisa becomes less transparent as she gets to know her and after Seisa gets used to the attention, she gets annoyed when Eruna pays more attention to other girls. They are both very important to each other and Eruna is a big part of Seisa's character development.
As said person who knows another person put it
My suggestion though, don't expect too much but still hope for the best~ ;)