Aaron Boreal

Aaron Boreal, known as Mamoru Amachi (天地 守) in Japan, is a good friend of Kelvin Stelar, Geo's father, and is the head researcher and founder of AMAKEN (天地研究所).

Personality
Aaron is a friendly and generous worker, as he tends to make friends with others co-worker and regularly shows cares to them, often asking about their works and resolve their distress when they need. This side of him is also explored in the way he treated with Hope Stelar like a good friend of him and Geo, in a way, like his own son, cheers him up in the most saddening moments of his life, especially when it's about Kelvin.

Mega Man Star Force
Aaron delivers the news of Kelvin's disappearance to Geo and his mother, and bestows upon Geo the Visualizer that was left to him by his father.

Later on, he invites Geo to check out AMAKEN, however, this goes awfully wrong. This is because Tom Dubious, in the form of Cygnus Wing, believes Aaron took credit for his invention, the FlapPack He then traps Aaron, Geo's friends, and other visitors in a space simulator, and they start running out of breath. When Megaman defeats him, Aaron asks him why he is doing this to him. Tom said that he lost trust in society, and talks a bit about his past, and wants him to take off his helmet to prove he trusts in him, since he claims to have filled the simulator with oxygen. He does it, and the two became brothers and good friends again.

Aaron also assists Sonia Strumm with her getaway from her boss by letting her stay at AMAKEN for the night, but he ended up finding her, and took her away.

He later aids Geo in reaching a space station to prevent the FM King from destroying the Earth by using a transmitter in its debris on Dream Island. He finds out that Geo is Mega Man when Omega-Xis comes to him for help.

Mega Man Star Force 2
Aaron contributed with the creation of the Star Carrier and appears in a Shopping Plaza where it is being sold. Geo sees him in the plaza and they have a short conversation. Later, he helps Geo upgrade his Star Carrier and gives him a Blank Card. Before Geo goes to Mu, Aaron sends a mail for him with a Giga Card.

Mega Man Star Force 3
Geo wants to help potentially resurrect Luna Platz, and Geo's mom, Hope Stelar, says she found Aaron at Alohaha recently, and he may be able to help. Sure enough, Aaron is there with the Satella Police, looking into the Strong incident. He resurrected Strong, but he admits that he is not himself, since too much of his data fragments were scattered after Joker's attack, and they couldn't recover all of it. He says they could ask Dr. Goodall, but before Geo leaves, he warns him that Noise is something that they are still unsure of, so if he feels even a little funny, he should stop.

Etymology
English:

The name Aaron is thought to be derived from Hebrew, suggesting its meaning to be "high mountain" or "exalted."

His surname name, Boreal, has several meanings. Its etymology is from the Latin borealis, northern, from Greek (Boreas), personification of the north wind. As he works with space science, it's possibly a pun on the Aurora Borealis effect or one of the Borealis constellations.

Japanese:

His forename Mamoru means "protector" or "to protect", and his surname Amachi means "Heaven and Earth."

Trivia

 * Aaron's role in the story can be seen as parallel to Yuichiro Hikari's, Lan's father in Mega Man Battle Network series. They both have a deep caring relationship with the protagonist, are the heads of important technological research facilities (SciLab and AMAKEN), and use their knowledge to aid the main character.