"Unyu?" (うにゅ?) has become her trademark sound, ever since she said it in the Extra Stage back story.
Because Utsuho is manipulated by Kanako, seems to have a simple and boastful personality, and is called a birdbrain by Orin, she's often considered an idiot by fans. ZUN also indirectly calls her an idiot in her theme song's description. This leads to comparisons (or pairings) with Cirno, and as the stage 6 boss, Utsuho is sometimes called ⑥ (which is an inverted ⑨).
Her arm cannon in UNL has led to fans parodying the Mega Man games with her. She's also shown in one fan work to have a crush on Bass.