Yes
She likes to think of it as a final thank you from her fans.
She also admittedly likes when her boobs get bigger

Despite her size, Maika is still a good swimmer. Most people are surprised with how fast she moves

Maika is a part time nurse and Swim teacher/lifeguard during the summer

No.
She finds it one of her Charm Points.

She also loves when her Father picks her up and hugs her

She'd never admit it, but no one showing up to her 8th birthday party before Maika showed up

Nowhere specifically
She just travels around the sea

She wants a new one piece swimsuit.
Her old one finally gave out

Lyra would probably try to eat Mira, then Mira would bonk Lyra on the head then do the same but succeed.
Mira's a lot stronger despite how meek she might be and tends to eat monsters whole.

People who litter on the beach or in the ocean.
If she sees you do it she'll immediately gulp you down

Don't. She rolls over in her sleep and has a tendency to sleep eat

As long as they don't bother her to much she won't mind and still stay asleep. You could probably sleep on her belly or boobs if your lucky

She's likes to show off in the ocean to people by jumping out of the water.
She'll also fall asleep on the beach. She loves the feeling of warm/hot sand

Yummy snack for the whale girl

No.
She never found the need too and hates physical activity

Gigantic boobs smacking them at a high speed