possible future characters to accompany others
- 07-Ghost: Castor for ? (Reine)
- Death Note: Mello for Matt (Maya)
- KHR: Lambo for ? (Piipa)
- Nabari no Ou: Raimei for Raikou (Piipa)
- Saiyuki: Nataku for a Goku (maybe Athena's)
Other suggestions that aren't as likely until I've read/watched more:
- Taki from PoT (Reine)
- Masato from UtaPri (Reine)
- Edge from Suikoden III (Reine)
- some character from Di[e]ce (Reine)