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- - - - - - - - - /// Ail

Ail
is one of the aliens born from Makaiju and surviving the fall of his
people. He came to Earth with Ann and Makaiju, where he and Ann disguised
themselves as two new exchange students in Usagi's school. As a human, his
identity is of Ginga Seijurou, the brother of
Ginga Natsumi (Ann's alter-identity). He was quite popular,
as all exchange students in anime tend to be. Many of the girls in
Usagi's class swooned over him.
While on earth, Ail grew a crush on Usagi and tried to win her over many times, always failing. Usagi was too busy trying to get Mamoru to remember his memories to pay attention to him. Ail uses a flute to call his Cardian minions to gather energy for the Makaiju, which is why he and Ann came to Earth. With the energy collected from humans, they're able to sustain both themselves and Makaiju.
During Ail's show of affections to Usagi, Ann got horribly jealous. Of course, she had no right to, since she was busy chasing Mamoru and clinging all over him. Though these two wouldn't admit it and they were both busy chasing around other people, they love and care for each other. That is what they found out at the end of the season.
- - - - - - - - - - /// Ann

Ann
is the only other alien born from Makaiju to survive the fall of her
empire. She and Ail came to Earth in search of energy from humans to sustain Makaiju and themselves. Though this was
their goal, Ann helped little in getting energy.
Often times, she gave Ail a harder time rather
than helping him. Her fits over Mamoru
and catfights with Usagi weren't helpful in the
least, and left all the work to Ail.
Ann instantly got a crush on Mamoru when she arrived on earth, and tried to win him over from Usagi. She didn't succeed, and in return got fiercely jealous when Ail had a crush on Usagi. Both denied that they had crushed on two other people, and at the end they finally stopped and realized that they were both meant for each other.
- - - - - - - - - - /// Makaiju
Makaiju is the tree that bore all life forms for his empire. When the empire fell, Ail and Ann, the only remaining children, took him to Earth for energy to not only sustain themselves and Makaiju, but to destroy the humans and make a new colony on Earth.
However, this was exactly the opposite of what Makaiju actually wanted. It wanted its children to grow with love and happiness, but instead they grew and supported themselves with hate and stealing human energy. When Ail and Ann finally realized that they were going in the wrong way about things, Makaiju turned into a new seedling and they took it to search for their own planet in order to start anew.