A man in Japan paid 600,000 yen (US$4,000) for a dream date with his favourite idol, only to discover that a bodyguard she had in tow was her husband.

Touka Toozuki, an underground idol from Tochigi prefecture, north of Tokyo, is known for her petite frame and sweet looks.

Unlike mainstream pop stars, underground idols perform in small local venues and manage themselves without big talent agencies.

Underground idol Touka Toozuki poses for her fans under an umbrella. Photo: Handout

Underground idol Touka Toozuki poses for her fans under an umbrella. Photo: Handout

Toozuki has built a following of more than 80,000 on social media, where she describes herself as living with two cats.

In October, a fan known online as Nino went viral after sharing his experience with Toozuki.

He claimed to have adored the idol for four years, spending millions of yen on her photo books and other activities to support her career.

In April, Toozuki offered fans a “Disneyland one-day date” experience.