yeah, this feels like a strange thing to pull when one of the major conflicts is that it IS a love triangle.
But then again, watatabe has the same framing but kinda shuffles Miko to the side for Shiori pretty quick. However, they make Diana's love for Natalie a focal point here.
Like the central tension IS that shes being torn between the sweetheart and the badgirl villainess But even then you can argue she only loves the idea of Lapis too. That all the girls see an idealized version of the girl they love but not the girl in front of them