Belphegor was known to be rather possessive, but that only got worsened when he got jealous. You were his and his only. Nobody else should have been able to even breathe near you. So you can reckon he wasn't too happy after you went shopping without him. Augh.. all the people who could have wanted you. It drove him insane. He sleepily clung to you, kissing your neck gently, but with a slight agression.