A California roommate agreement defines an arrangement between people occupying the same residence. No information is available for this page.Project Sentinel, a nonprofit agency, provides information and dispute resolution services to tenants, landlords, and roommates. It is not illegal to be an occupant who is not on the lease. However, it probably violates the terms of the lease that they signed. This housing contract is not a lease and is not subject to California Landlord-Tenant laws. A roommate agreement is not binding on the landlord. A lease or rental agreement is an important document that can address important issues regarding tenancy such as: How long is the tenancy period. This housing contract is not a lease and is not subject to California Landlord-Tenant laws. I talked to the initial landlord this morning, and she said I can move out anytime because the sublease between my roommate and I is not normal.