Seiji Aizawa is one of the supporting characters in the anime series. He is Minto's older brother.
Seiji watched Minto's ballet recitals when he was younger. However, he was too busy attending his private school and getting involved in the corporate world to pay any attention to Minto.
Tokyo Mew Mew
In episode 9 of Tokyo Mew Mew, Ichigo made a plan to have Seiji attend one of Minto's ballet recitals. He didn't want to, but he did. Suddenly, a Chimera Anima, which was ballet-themed and made from a black swan, attacked him. He tried to protect Minto, but was knocked out. Minto defeated the chimera anima in the end before her recital, and Seiji told her she was still important to him. He gave her some flowers and watched her ballet recital.
- Mew Mew Power - Sergio Bucksworth
- Mew Mew Amiche Vincenti (Italian) - Sergio Aizawa
- Dong Jing Mao Mao (Mandarin) - Shì-Sī LánZé
- Berry Berry Mew Mew (Korean) - Minseo Ju
- Seiji's english voice actor, Jason Anthony Griffith, is famous for voicing Sonic and Shadow the Hedgehog from Sega's famous Sonic The Hegdehog series. He provided their voices in the Sonic X anime, which was dubbed by the same company that dubbed Tokyo Mew Mew (4Kids Entertainment ).
- He was described by Lettuce and Ichigo to be tall and handsome.