OVA: Is That an Inkflatable Pool?/Squidn't Your Mom Stop By?/Is That a Message Ink a Bottle? Shinryaku! Ika Musume : Season 3 Episode 2

Musume wants an inflatable pool in the garden, since that is much easier to inkvade - lifeguard Gorou's oasis of tranquility, close to Chizuru at the Lemon House by the Sea beach restaurant, is rudely invaded when his mother shows up - and to further her world-wide inkvasion Musume decides to send out a message in a bottle.