Masaya Aoyama (or Mark in the English dub) is Ichigo Momomiya's classmate and love interest in the Tokyo Mew Mew series. He is voiced by Megumi Ogata in Japanese and Scottie Ray in English.
Masaya is Ichigo's classmate. At the beginning of the series, he and Ichigo go on a date to the red data animals exhibit where Ichigo met the other Mews and became a Mew Mew herself. At first, she thought Masaya was oblivious to her feelings, but he later reveals that he shares her feelings and they begin dating.
Masaya is the only person outside the Mew Project to know Mew Ichigo's real identity, but initially pretends otherwise as he knows Ichigo does not want him to know. He was supportive of it when she finally told him in episode 38, and said he would help her hide it.
Towards the end of the series, Masaya reveals that as an orphan, he began acting like a "perfect child" to be adopted. In reality, however, he felt sick of humans and disgusted by how they treat the planet. He also reveals that Ichigo is the sole exception, and it was only with her that he felt like a "real human being".
As the series progresses, it is revealed that Masaya is the Blue Knight, but Masaya did not know that he was the Blue Knight, nor did the Blue Knight appear to have any knowledge that he was Masaya. Once Masaya becomes aware of his transformation, he realizes it was born of his desire to protect Ichigo. Shortly after this revelation, Masaya collapses and reawakens as Deep Blue, the leader of the aliens and the Mew Mew's final enemy.
Deep Blue claims that he created Masaya in order to deceive the world until the time was right for his awakening. Masaya sacrifices himself by releasing the final Mew Aqua inside his body in order to stop Deep Blue, and is revived when Ichigo gives her life to save him. In turn, the mew aqua remaining his body then saves her.
At the end of the series, Masaya decides to go to England to study the endangered species used for the Mew Project and the Mew Mews hold a mock wedding for Masaya and Ichigo before he leaves.
Ichigo describes Masaya as "smart", "cute", "very athletic" and "popular at school". He is also depicted as being a polite and calm person, and will protect Ichigo at any cost when he transforms into Blue Knight.
The truth is that he despised the human race ever since he was a child. Everything he did and said was just an attempt to blend in and be accepted. However, once he started to spend time with Ichigo, he began to soften and changed his view of humans. He's noted to be very eco-friendly and an animal lover since he participates in recycling and using environmentally-friendly material.