For this academic event, our department was honored to invite Professor Kei Ishiguro from the National Institute for Japanese Language and Linguistics (NINJAL) to deliver a guest lecture. Professor Ishiguro introduced the characteristics of Japanese youth slang from two dimensions: language evolution and the nuanced differences resulting from various vocabulary choices. The lecture featured a wealth of contemporary examples. Notably, Professor Ishiguro's daughter, Ms. Ai Ishiguro, who is currently a university student, also attended the event to share firsthand insights into the precise meanings and usage of modern youth terms. Furthermore, from the perspective of language change, the professor systematically classified youth slang into categories such as "temporary fads" and "regional slang." During the Q&A session, students actively engaged with the speaker, and everyone in attendance walked away with a wealth of knowledge from Professor Ishiguro's brilliant presentation.