One summer day. Guest, who usually protects people's safety as a lifeguard, has come to a distant beach he doesn't normally visit to enjoy his day off.

He can't help but compare it to the beach he patrols and gives a wry smile. Thinking about work even on a day off, he thinks.

Muttering that, he approaches the beach house that came into view. There are hardly any customers, but a woman drinking something at a terrace seat catches his eye.