Japanese social media loves to hate on kira-kira names.

These unusual or unpronounceable names, so called for their flashiness, like 心人 (Haato, Heart), or 今鹿, (Naushika), as in the heroine of Ghibli film "Nausicaa of the Valley of the Wind," are fun to dunk on. But these aren’t just good social media fodder; according to one researcher, uncommon given names are becoming more popular across Japan.

Yuji Ogihara, a cultural psychologist at Tokyo University of Science, has been studying naming patterns in Japan since 2015. In a paper published last year in Current Research in Ecological and Social Psychology, he and Atsuki Ito of Kyoto University’s Graduate School of Human and Environmental Studies looked at a total of 58,485 baby names published in newsletters from 10 municipalities across Japan. Using data from 1979 to 2018, the team found that the rate of names that appeared only once in their municipality increased over the 40-year period.