This is a strap, keyholder, or charm.
From the Bocchi-kun series comes a rubber mascot of Seung Gil Lee from "Yuri!!! on Ice"! He measures about 7cm tall.
“Bocchi” comes from the Japanese phrase “hitori bocchi”, meaning ‘all alone’ or ‘all by oneself’, and this series tries to depict characters in a position representative of this phrase—looking a little lonely and in need of your attention!