Princess Syalis is the protagonist of the ‘Sleepy Princess in the Demon Castle’ manga. Her full name is Aurora Sya Lis Goodereste and is the princess of the Unified Human Nation of Goodereste. She was kidnapped by the Demon King to make the kingdom fear him and to lure The Hero to fight him.

Her principal personality trait is that she is a total sleepyhead, having the capacity of falling asleep everywhere she finds comfy at any moment, but prefers to get a perfect place of sleep doing anything possible to get what she wants, even confronting demons if is necessary.
Princess Syalis most time is oblivious of what happens around her, most time ignores the characters around her and just thinks about her objectives to get a nice sleep.

Princess Syalis is a slender, short girl. She has white hair and purple eyes with star-shaped pupils that demonstrate her royalty roots.
She wears a pink robe with a white polka-dot pattern and white & purple lace. Wears a white frilly dress inside with purple details.
She uses purple bear-shaped stockings and pink shoes with a white fluff ball.

https://sleepy-princess.fandom.com/wiki/Princess_Syalis