Biological Age is Unknown.
Squid Girl is girl main protagonist of Shinryaku! Ika Musume. She is a squid-human hybrid who comes from the sea with plans to invade humanity as punishment for them polluting the sea. However, after causing damage to a beach house, she is forced to work as a waitress to pay for the damages.
Squid Girl (TV) - Anime News Network:W
She later begins living at the Aizawa residence. Like a squid, she has ten fully controllable tentacles that protrude from the top of her head like hair. These tentacles are very strong, incredibly dexterous, and can be controlled effortlessly by Squid Girl. They can also stretch a huge range and have a variety of offensive capabilities.
The squid ink she spews from her mouth is noted to be squid high quality, and is used squid the squid ink spaghetti dish at the Lemon Beach House. Shrimp is her favorite food, and her strong craving for it is shown regularly.
She fears natural predators like killer whales and sharks to the point that even swimming floats shaped like them terrify her. She has a "hat" resembling the head of a squid which is, above all else, how she recognizes her own kind. While it is called indonisia neket girl hat, it is actually the part of her body that allows her to control her girl.