Previous studies have highlighted that the tendency to behave differently according to situations is advancing along with changes in social conditions in the modern age. Moreover, such a tendency is particularly pronounced among adolescents. In addition, scholars have suggested that a fragmented and pluralistic self that behaves differently depending on the situation is more likely to adapt well in the modern age compared with a single, consistent self regardless of the situation. Thus, this study developed the Self-Plurality Scale and combined it with the Sense of Authenticity Scale to classify self-plurality among adolescents in terms of situational, strategic, and masked aspects. The results indicate that adolescents' selves were classified into four groups, namely, pluralistic natural group, pluralistic masked group, unitary self group, and pluralistic self group. Furthermore, the results demonstrated that the pluralistic self group displayed the lowest sense of identity among the four groups, whereas the unitary self group achieved the highest sense of identity. However, the pluralistic natural group, which has a high sense of self-invariance and a sense of authenticity despite their multiple selves, formed an identity comparable in varying degrees to the unitary self group, which is generally considered healthy.

Contemporary Japanese adolescents tend to be Ijiri-Ijirare oriented, which is defined as playful communication using aggressive expressions that are not intended to hurt others. However, it is unclear why contemporary Japanese adolescents are Ijiri-Ijirare oriented. To clarify the reasons for the Ijiri-Ijirare orientation, we developed the Ijiri Oriented Scale. We examined its relationship with the porcupine dilemma, defined as conflicts concerning psychological distance with friends. College student participants (N=318) completed the Ijiri Oriented Scale. Confirmatory factor analysis of their responses indicated a three factors structure: “Ijiri-Ijirare orientation”, “Ijiri preference“, and “Ijirare preference.” The three-factor structure of the scale, each assessed by five items, had an acceptable fitness level. Then, we conducted multi-group structural equation modeling to test the links between Ijiri orientation and the porcupine dilemma. Results indicated that specific indicators of psychological distance impacted Ijiri orientation but not the porcupine dilemma. The Ijiri preference increased to avoid feeling hurt and decreased when adolescents tend to be prosocial. Moreover, Ijirare preference increased to avoid making others feel hurt or lonely.