The agreements, announced Monday by general manager Mickey Loomis, are all for four years.
Kikaha, an edge pass rusher who set career and single-season records for sacks at Washington, was the Saints' second-round pick. Grayson, who played at Colorado State, was a third-round choice.
The other four players who've agreed to terms include three fifth-round picks: Chattanooga outside linebacker Davis Tull, Fresno State defensive lineman Tyeler Davison and Georgia cornerback Damian Swann. Missouri running back and return specialist Marcus Murphy, a seventh-rounder, also has agreed to contract terms.
The Saints open a three-day rookie camp on Friday.
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