Tenant out, girlfriend still in the house

[Roy Gutierrez]

Hi guys,

The lease with my tenant ended but he paid for an extra month (last month is may), he had a fight with his girlfriend (she's not on the lease), he moved out and she stayed. I asked tenant to make sure she leaves at the end of the month, of course he says 100%. My question is what happens if she decides she wants to squatter? Is he obligated to pay another month? or am I stuck trying to evict her?

Thanks!