You got a gashapon and it came with a little ball chain. You got an acrylic keychain and it came with a big keychain thingy. You'll need to tweak these a bit to get them into your bag.
We've got you covered. Co-Kan Brand clasp adapters are a simple solution - clasps on easily bendable jump rings. Just open the jump ring with your fingers, and attach to the charm in question. Now you can easily put any charm in your bag!
Comes in a pack of 6 for your decorating pleasure.