Fan-Preferred Couple: Yvienne/Lariatte tends to be this, to the point where an entire scanlation group ended up dropping the series when Yvienne ended up developing feelings for Krohiten instead.
Ho Yay: Between January and Daughter, to the point where 'Heterosexual Life-Partners' really just isn't a fit term for them. It ends up going from subtext to text at the end of volume 14, at which point they decide to run away from the king and Lowood to spend their lives together.
And Tenial's interest in January comes across as little too personal for a king and his subordinate.
Les Yay: To some degree between all pairs of witches. It's pretty explicit with the upperclassmen, Judith and Ecliche, whereas with Yvienne and Lariatte it varies from heavy to light at different points.