Only one in five high school boys in Japan say they have had their first kiss, the lowest ever figure recorded in a regular survey on youth sexuality.
The study by the Japan Association for Sex Education (Jase) has been done every six years since 1974.
High school girls are also demure with 27.5%, or more than one in four, saying they have had their first kiss. But the decline among boys was much higher compared to the last survey.
The numbers show how pandemic restrictions have affected how Japan's youth express themselves sexually, experts say.
Fewer Japanese youths are having sex, the study also showed.
The ratio of high school boys who say they have had sexual intercourse fell 3.5 points from 2017 to 12%. For high school girls, it declined 5.3 points to 14.8%.
The Tokyo-based Jase polled 12,562 students across junior high schools, high schools, and university in 2023 for its study.
School closures and restrictions on physical contact during the Covid pandemic had likely impacted many of these students, as it happened "at a sensitive time when [they were] beginning to become interested in sexuality", according to Yusuke Hayashi, a sociology professor at Musashi University quoted in the Mainichi newspaper.
While they are less active with partners, the survey found that masturbation is rising across all three demographics and is at record high levels among junior high school girls and high school students in general.
The survey results come as Japan struggles to arrest its falling birth rate and a growing problem of sexlessness. A separate survey earlier this year found that nearly half of marriages in Japan are sexless.
The country has the world's oldest population, measured by the UN as the proportion of people aged 65 or older.
In late 2023, Japan said that for the first time one in 10 people in the country are aged 80 or older.
In March, diaper-maker Oji Holdings announced it would stop making baby nappies to focus on making adult diapers.
