Young and lustful, this guy might already be in a relationship with Corinna. In any case, he's super anxious to get her outside and into the May Day scene.
But he's also a philosophical dude. May Day isn't just about flowers and cakes and sexy times. In this poem he also expresses a whole way of life that elevates community, puts nature alongside religion, and stresses the importance of living in the moment.
This is about the "we" and the "now" rather than the "I" and the "later."