Management at a shop has begged guests to shower before visiting after seeing an "increase in the number of customers in an unhygienic state".
Bosses at Cardland, a collectable trading card shop in Akihabara, Tokyo, even warned visitors they won't be allowed to participate in gaming tournaments it holds regularly if their hygiene is below-par.
And the shop has even vowed to give these customers free detergent in a thinly-veiled hint to clean their act.
The stance has divided opinion somewhat, with some customers applauding Cardland for helping achieve "true peace in our world". Others have blasted the business for "shaming people" and suggested those given the Oxiclean detergent may not ever use it anyway.
The shop said in a tweet: "The weather has become much hotter with the recent sudden jump in temperatures. With that, there’s been a small, but noticeable, increase in the number of customers coming to our shop in an unhygienic state.
"We ask that customers thoroughly shower before coming to the shop and arrive in a clean state, especially when we are holding in-shop tournaments and many people will be sharing the same enclosed space for an extended period of time."
Oxiclean provided Cardland a huge package of its products for free when it saw the shop's tweet.
Cardland has kept them in the box, ready to dish out to hapless punters.
June is typically a "rainy season" in Japan but temperatures in late May in Tokyo exceeded 25C. The shop believes this has caused customers to have become particularly "sweaty".
Forecasters, though, believe the mercury will continue to top 20C in early June in the city.
