Ran Ryuuren

He is the youngest of the five brothers of the Ran family. He is eighteen years old. It is said that, out of his four older brothers he was the most worthy of the name Ryūren Ran because he is a genius.

He calls his older brothers foolish and doesn't call them by their name, rather: Shūei, "foolish elder brother the fourth". Recently, he's called Shūrei, Soul Friend #1, and Eigetsu, Soul Friend #2 (He refers to Yōgetsu as Soul Friend #2.5).

He does things on his own time and is quite impulsive: when he was going to buy ingredients for chicken stew with Shūrei, he ended up buying soy beans, then he traded that for boiled eggs, then traded the eggs for spring onions, then the spring onions for wood blocks, then flowers, then fish, then straw, and then he gave away the straw to a little girl and just ended up with one stalk of straw.

Later in the series, he goes ghost hunting after hearing about a late-night ghost. He also pulls out his flute and plays it without warning, often off key. Since he can't be easily told what to do and is very unpredictable, he's necessary in the Ran family. Although, because of this behavior many find him weird and annoying, so they usually distance themselves from him. Shūrei was the only one who put up with him, so he said that she's now his soul friend.

He travels to different places playing cards, but is only allowed to wander around if he takes the official exams and finishes in the top three. He wanders off again and is finally seen again taking the final exams with Shūrei and Eigetsu. He declares that Eigetsu is also his soul friend since he's Shūrei's friend. He passes the Official Exams with the second highest score, taking the "Bougen" spot.

More on Ran Ryuuren here.