Ohio Rev. Code § 2305.29: No civil liability for breach of a promise to marry, alienation of affections, or criminal conversation.

No person shall be liable in civil damages for any breach of a promise to marry, alienation of affections, or criminal conversation, and no person shall be liable in civil damages for seduction of any person eighteen years of age or older who is not incompetent, as defined in section 2111.01 of the Revised Code.