34x7 - Kamen Rider

A boy appears in front of Houtarou and others, asking to take over Saboneedle. Since Ordinary people and Chemies cannot coexist, Rinne, who values the rules, tries to accept the boy's request, but Houtarou is not convinced. Doesn't he really want to be with Saboneedle? Houtarou tries his best to find out the boy's true feelings, but then a new Malgam appears. What is the true identity of Malgam who is targeting the boy for some reason!?