Hi - my name is XXXXX XXXXX I'm an Intellectual Property litigation attorney. Thanks for your question.
Copyrights protect “original works of authorship” that are fixed in a tangible form of expression. The fixation need not be directly perceptible so long as it may be communicated Copyright Basics with the aid of a machine or device. Copyrightable works include the following categories:
1 - literary works
2 - musical works, including any accompanying words
3 - dramatic works, including any accompanying music
4 - pantomimes and choreographic works
5 - pictorial, graphic, and sculptural works
6 - motion pictures and other audiovisual works
7 - sound recordings
8 - architectural works
A trademark includes any word, name, symbol, device, or any combination, used, or intended to be used, in commerce to identify and distinguish the goods of one manufacturer or seller from goods manufactured or sold by others, and to indicate the source of the goods.
So, in your case if you want to protect only the character, you only need a copyright. However, if you want to protect any goods or products by you using the symbol of your characters, then need to file for a trademark.
Thus, you can apply for both, but the copyright will protect the creation of your character. I hop this answers your question, but if you have others, please REPLY and I'll be glad to respond. Thanks.