Following a hiatus due to COVID-19 restrictions, study abroad programs continue to be promoted by Japanese universities as beneficial for acquiring English and fostering global human resources. While prospective sojourners primarily consider inner-circle destinations, such as the United States and Australia, outer-circle countries receive significantly less attention. Therefore, this article is based on a longitudinal, transcendental phenomenological study, funded by the Japanese government, involving the shared experiences of six Japanese university students who studied at a university in Bangkok, Thailand. The authors' main purpose is to better understand the experiences of Japanese students in Bangkok, so that educators can improve language and culture curriculum for students intending to study in outer and expanding-circle countries, potentially increasing access and participation. The six participants completed weekly journals over 10 weeks while in Bangkok, followed by a post-return reflective survey and semi-structured interview. To capture the essence of experience, the authors identified 403 significant statements resulting in two clusters of meaning that compose a textural description of experience: utilizing English as a Lingua Franca and exposure to diversity (e.g. openness of sexuality and socio-economic disparities). A more nuanced structural description involves the four clusters of developing intercultural communicative competence; empathy; appreciation of one's home country; and challenging predeparture beliefs of the destination. After defining the participants' essence of experience and their impression of diversity, the authors provide pedagogical implications that can help institutions improve the curriculum of pre-departure programs, especially for students who eventually enroll in international experiences outside the Inner Circle.