Ohio Rev. Code § 1341.04
A person bound as surety in a written instrument for the payment of money or other valuable thing, if a right of action accrued thereon, may require his creditor, by notice in writing, to commence an action on such instrument forthwith against the principal debtor. Unless the creditor commences such action within a reasonable time thereafter, and proceeds with due diligence, in the ordinary course of law, to recover judgment against the principal debtor for the money or other valuable thing due thereby, and to make by execution the amount thereof, the creditor, or the assignee of such instrument, so failing to comply with the requisition of such surety, thereby shall forfeit the right which he otherwise would have to demand and receive of him the amount due thereon.
R.C. §1341.04