Sekirei S01 E05 The Water Sekirei

The mysterious girl turns out to be Matsu, a Sekirei who has been hiding at the Inn. Matsu becomes Minato's third Sekirei. Minato has dreams of another Sekirei, later identified as Tsukiumi, a Sekirei that despises Ashikabi. Minato and Kusano go looking for her and encounter Seo. Hikari and Hibiki soon arrive chased by Tsukiumi.