In astrology, horoscope is a diagram which shows the positions of the planets and other celestial bodies at a given moment; such as the moment of a person's birth. The word "horoscope" comes from the greek "horoscopos".

• The Archer, Sagittarius (Die)
• The Water Carrier, Aquarius (Kaoru & Kyo)
• The Ram, Aries (Toshiya)
• The Fish, Pisces (Shinya)

Western people date the years from the birth of Jesus Christ, for example, 2004 means 2004 years after the birth of Christ. This represents a linear perception of time, with time proceeding in a straight line from the past to the present and the future. In traditional China, dating methods were cyclical, cyclical meaning something that is repeated time after time according to a pattern. This pattern is the 12 Twelve Animal Signs, which are, in order: the rat, ox, tiger, rabbit, dragon, snake, horse, sheep, monkey, rooster, dog and pig (Japanese zodiac includes the wild boar instead of the pig). Therefore, every 12 years the sign would reappear.

• The Tiger, Tora (Die & Kaoru)
• The Dragon, Tatsu (Kyo)
• The Snake, Hebi (Toshiya)
• The Horse, Uma (Shinya)

Dismissed by many scientists as superstition or pseudoscience, it is popularly believed in Japan that a person's ABO blood type is predictive of their personality, character, and compatibility with others. This belief has carried over to certain extent in other parts of East Asia such as South Korea and Taiwan. In Japan, asking someone their blood type is considered as normal as asking their astrological sign in other countries.

• A (Kaoru)
• B (Die, Kyo, Toshiya, Shinya)