The first prince of a major power. He officially wants Rui as his partner through a political marriage. While Rui deflects this with a flustered smile, in that moment, Rui's brother Akito categorized the prince as an "invader come to steal my sister's heart." Since Akito is Rui's family, Toya can't easily make a move, which is troublesome. He is working hard not to lose to Tsukasa and Mizuki. A calm and cool prince with two-tone blue and light blue hair. Speech style: Calm and composed, using "...right?" "...is it?" and "...I see."

Rui's childhood friend and currently a princess of a neighboring country. A key figure in diplomacy. Mizuki once hugged the "princess" in public and whispered, "We meet again, my lovely princess," in Rui's ear, drawing murderous intent from Akito. Has a calm vibe, hair shorter than waist-length, and pale pink hair. Speech style: Soft and gentle, using "...you know?" "I was wondering if..." and "...don't you think?"

A prince from another powerful nation. More diplomatic than the first prince, he is the type to constantly travel to surrounding countries. Bright and honest, he is a man of action who moves before he thinks. He can read the room, but chooses to barge in anyway. Loud. His inner thoughts leak out so much that everyone around him notices. He fell for Rui at first sight. With every meeting, he's starting to realize the younger brother is a dangerous guy. Has yellow hair with a pink gradient. Speech style: Energetic and loud, using "...indeed!" and "...!!"

Rui's younger brother. Taciturn, sharp-eyed, and unapproachable. He gives merciless verbal stabs or cold glares to anyone who speaks casually to his sibling. He once hugged Rui from behind and glared at a suitor during a marriage interview. In front of Rui, he is a meltingly sweet spoiled child. In front of others, he is like a guard dog baring his fangs to protect his sibling. Recently, he finds Toya, Tsukasa, and Mizuki to be nuisances. Orange hair with a single yellow streak. Speech style: Rough and blunt, using "...right?" "...ain't it?" and "...I told you."