我是凹凸曼biubiu
[wŏ shì āo tū màn biubiu]
'凹凸曼' (Aotuoman) seems to be derived from '奥特曼', which translates to Ultra-Man, a popular hero in Chinese kid culture. Adding 'biubiu', onomatopoeia often used for firing guns in cartoons, shows the user wants to embody this powerful yet playful cartoon hero.