Straddled vehicle

A straddled vehicle, comprising:

• a vehicle frame;
• a main seat located above the vehicle frame;
• a tandem seat located above the vehicle frame and to the rear of the main seat;
• an accommodation portion provided below the tandem seat;
• a seat lock mechanism attached to a bottom portion of the tandem seat, the seat lock mechanism detachably securing the tandem seat to the vehicle frame;
• and
• a lock portion formed in a front portion of the accommodation portion, the lock portion being attached to the vehicle frame and being engageable with the seat lock mechanism, wherein
• the seat lock mechanism includes:
• a key cylinder including
• a main body having a key insertion hole, for a key to be inserted therein, and
• an arm protruding from the main body, the arm being pivotable around the main body by a pivoting operation made by the key inserted into the key insertion hole, and
• a hook member configured to pivot along with the pivoting of the arm of the key cylinder, the hook member including
• a first hook portion engageable with the arm,
• at least one second hook portion engageable with the lock portion, and
• a pivoting restriction portion configured to restrict the hook member from pivoting in a state where the key insertion hole does not have the key inserted therein.