Nabi: The Prototype

From Tokyopop:
In this collection of cute shojo stories, Ryu-Sang is a tough boy who gets in fights and--although he doesn't want to admit it--cares for the girl he's supposed to protect.

Story 3: Myo-Un, an orphan girl with no memories of her past. Tells the story on how she came to understand the bad mannered boy Ryu-Sang to which became her first friend in the temple.
Story 4: Ryu-Sang, a mean and blunt orphan boy. Although he hates and treats Myo-un badly, he protects her!?
Story 5: Aru is a child who just lost her father, the story on her journey to the temple while being accompanied by big brother Ryu-Sang and older sister Myo-Un.

Note: Myo-Un and Ryu-Sang are both the protagonist in the series Nabi, one of the author’s ongoing series at the moment.