The beach... (spoiler)

Not surprised because that would have been in a way an admission of his attraction to Phil. However the entire hazing scene had a kind of BDSM feel so in a way Len was living out his fantasy on some level.

Between what Len does to Phil and what he forces Phil to do to himself, it's definitely a sexual assault. Len won't do anything actually explicitly sexual, because like the poster above says, that would be admitting his attraction.