Read the lease as broadly as possible to see if any language applied to removing the furniture could be used to evict you for breach of contract.
Strictly speaking, squatters do not need to be formally evicted, that is served with notice and sued in unlawful detainer.
To paraphrase David Mamet, the landlord business is a people business. It’s a fucking people business.
San Francisco is expensive and many landlords these days want to cash in on the new Twitter/tech boom. One of the easiest ways to remove rent-controlled tenants is to sue them for illegal subletting.
Your landlord pulled one of the oldest, dirtiest tricks in the landlord playbook. We in the business call it “sewer service.”
Your landlord may not be required to give you permission to let your boyfriend move in.
It’s never a good idea to try to backpedal to get a landlord’s consent to the addition of a roommate after the roommate has moved in. Follow the rules before you add a roommate.