Study of Otaku has a lot of speculative researches but few quantitative ones. We conducted the questionnaire research for 681 students in five universities to estimate the degree involvement in Otaku activities. The results are as follows: 1)Four factors are detected which are self-affirmative enthusiasm to hobby, collector, sympathy toward other Otakus by sharing hobby interests, and paying no attention to fashion. these factors are classified into two groups: maniac activities and lack of communication skills. 2)There is no relationship one’s self-acknowledgement of Otaku and his social skills. 3)Two oppo- sites of Otaku exists. The one is Ria-ju repletion of real life, which is a Japanese internet slang for people who are sociable to everyone. The other is the man has low social skills and no motivation for anything.
