It was used to denominate Lords and Ladies in the Court, especially during the Heian period. The most famous example is the Prince Hikaru Genji, protagonist of "The Tale of Genji" who was called . Nowadays, this suffix can be used as a metaphor for someone who behaves like a prince or princess from ancient times, but its use is very rare. Its main usage remains in historical dramas. This suffix also appears when addressing lovers in letters from a man to a woman, as in .   literally means "above", and denotes a high level of respect. While its use is no longer common, it is still seen in constructions like , and , reverent terms for "father", "mother" and "older sister" respectively. Receipts that do not require specification of the payer's name are often filled in with "ue-sama". Martial artists often address their teachers as "sensei". Junior and senior students are organized via a "senpai/kōhai" system. Also in some systems of karate, "O-Sensei" is the title of the (deceased) head of the style. This is how the founder of Aikido, Morihei Ueshiba is often referred to by practitioners of that art. The "O-" prefix itself, translating roughly as "great[er]" or "major," is also an honorific. Various titles are also employed to refer to senior instructors. Which titles are used depends on the particular licensing organization.   are martial arts titles developed by the Dai Nippon Butoku Kai, the Kokusai Budoin and the International Martial Arts Federation Europe. Many organizations in Japan award such titles upon a sincere study and dedication of Japanese martial arts. The below mentioned titles are awarded after observing a person's martial arts skills, his/her ability of teaching and understanding of martial arts and the most importantly as a role model and the perfection of one's character. Levels of black belts are occasionally used as martial arts titles:   In informal speech, some Japanese people may use contrived suffixes in place of normal honorifics. This is essentially a form of wordplay, with suffixes being chosen for their sound, or for friendly or scornful connotations. Although the range of such suffixes that might be coined is limitless, some have gained such widespread usage that the boundary between established honorifics and wordplay has become a little blurred. Examples of such suffixes include variations on "-chan" (see below), "-bee" (scornful), and "-rin" (friendly).