GreenLeafMochi, here are some ideas for him: Becomes medicine cat apprentice and learns slowly but surely to like being a medicine cat. Some cat comes into his life and helps him heal his heart. They can later become mates. He could die.( This is an option but I hope you don't pick it.) Of course you can plan your own story for him. I can't wait to see this comic you are making! I hope it is successful! I know it will be great! If you need any help than I can help you if needed!
When he and his sister were kits they got very sick. The medicine cat was unable to save Shadepaw's sister and she died. Shadepaw now hates medicine cats and has a very hate filled heart. As a result, he tries to hurt the medicine cat with hurtful words and he is very short tempered. He can be a good cat, but he needs help from someone to heal his broken and hateful heart.