Saiki

No, Kusuo Saiki was not born a girl; he was born male but used his transformation power to appear female for a short period immediately before his birth, only transforming back into his male form an hour later. Saiki has maintained that his true gender is male, and he uses the female form out of convenience, not because he identifies as female. Saiki's first power was transformation, and he explains that he used this power while still a fetus in his mother's womb. Moments before his birth, he used his power to transform into a girl, which is why he was born physically appearing as a girl. This transformation was temporary, and he reverted to his original male form an hour later. Saiki identifies as male, and his use of his transformation power is for convenience, not a reflection of a transgender identity.

Saiki is canonically asexual, but not aromantic. In chapter 267, he includes himself in a relationship chart, saying he has a crush on Satou-kun.

Saiki is incredibly powerful, possessing nearly every form of psychic ability imaginable, including telekinesis, telepathy, time travel, mind control, and reality manipulation, placing him at least at a planetary level with potential for much greater power without his limiters. He desires a normal life, so he suppresses his abilities with limiters, but even with them, he can cause natural disasters. His full power, while rarely shown, could potentially be multi-planetary or even star-level. His abilities include Mental Abilities: Telepathy, mind control, hypnosis, memory erasure, and telekinesis. Physical Manipulation: Super strength, flight, size augmentation, and the creation of psychic constructs.

In The Disastrous Life of Saiki K., Saiki is 17 years old by the end of Season 3 (which concludes with Reawakened). He starts the series at 16, and the plot implies he has spent his time in high school as a consistent student, with the story ending when he is nearing the end of the second year of high school. Saiki begins the series at 16 years old and by the time the events of Season 3 conclude with the Reawakened specials, he is 17 years old. While Saiki possesses many psychic abilities and mentally experiences a lot, his physical age and the age of his classmates remain consistent with a typical high school experience. His birthday is August 16, making him a Leo.

Saiki possesses an extensive array of psychic abilities. These include telepathy, allowing him to read minds and communicate mentally, and telekinesis, which enables him to move objects with his mind. He also has the power of psychometry, precognition, astral projection, and the ability to manipulate emotions and memories. His powers are so vast that he often uses limiters to suppress them, seeking a normal life.