Legal Question in Landlord & Tenant Law in Washington

If the boyfriend paid for the deposit and rent, then he should, through an attorney, demand that she reimburse him for her share. He can sue her in small claims, and if you are willing, you can act as a witness for him to say that boyfriend paid the entire rent for both of them. (I assume he paid with a check from his own checking account. This is key, otherwise, you have no real proof who paid the rent and deposit.) If he does this, he needs to go through an attorney, otherwise, he will likely be in violation of the same protection or no-contact order. Also, if he contacts her through other third parties, such as yourself, that will also likely constitute a violation of the court's order.

Alternatively, the boyfriend can file a motion with the Court that entered the protection order to ask that he be allowed to live in the unit since the girlfriend lives elsewhere and he's already paid the rent. He'd need a signed declaration from you attesting to the fact that the unit is empty.

Separately, you may be able to evict the girlfriend if she does not inhabit the unit. This would be based upon an abandonment clause in your lease, if you have one. Many landlords keep abandonment clauses in their leases because they want the tenants to regularly occupy the unit rather than leave it empty for long periods which can result in mold, mildew, rusty pipes, criminal activity, possible squatters, etc.

You do not specify whether the boyfriend paid the all the rent for the entire lease term or just the first month's rent and deposit, but if there are remaining months on the lease, then another option is to wait until more rent is due, and demand that she pay it, but don't demand any rent from the boyfriend. If she cannot pay the entire rent at that time, she'll have no choice but to move or you'll evict her, after which time, the boyfriend can sign a new lease with you and move in on his own.

One word of caution to you, which I would give any landlord who is a client of mine. Tenants like the boyfriend who may appear to be nice guys caught up in bad situations that have them arrested for domestic violence tend to have issues that you as a landlord do not want to entertain in the long run. I would strongly advise you to consider just finding someone else to do this work and be your tenant.

Assuming for a moment that he is the perpetrator and that he has domestic violence issues, then I promise you, there will be more moments like this, more girlfriends whom he fights with and if the girlfriends have the guts, more cops and arrests.

Best of luck to you.