Mentioned Characters: Remilia, Flandre, Sakuya, Patchouli, Flan

This parallel-world Flandre Scarlet did not follow her usual fate. Her sister suddenly disappeared from her home world, causing her to leave on her own interworld journey. That's how she met the tiny Remilia Scarlet, whom she affectionately calls Big Sis. She formed the Remilia Guard to protect her, and as the captain of the guard, she will do anything―even swim to the bottom of the ocean―to keep her beloved Big Sis from harm.

This parallel-world Remilia Scarlet did not follow her usual fate. She's on an interworld journey to recover the fragments of fate that were stolen from her. However, she did not expect to end up in a world of eternal summer. She tried to adjust by equipping herself with sandals, a swimsuit, and a swim ring, but she didn't truly start enjoying this world until she encountered the drink of her dreams: barley tea. Now, this world is her oyster, and she's so excited to go outside and play that she sometimes forgets to put on both of her sandals.

The Remilia Guard is a martial organization with a hierarchical structure, and its members use any means necessary to protect Lady Remilia. The guard captain, Flandre, is a mighty fighter who eliminates most enemies before they can even get close to Remilia. However, since she cannot say no to her adorable but temperamental Big Sis, she sometimes places herself in extreme danger in an attempt to fulfill her impossible requests. It seems the biggest threat to Remilia's (and Flandre's) safety is Remilia herself.

"Flan? Sakuya?" "What's wrong, Big Sis?" Flandre, the captain of the Remilia Guard, was the first to react to the mistress of the Scarlet Devil Mansion's voice. While this Remilia and Flandre may live together in the same mansion, they aren't truly sisters. Flandre's actual sister was the managing director of a massive conglomerate that she built from scratch, until she suddenly disappeared one day. Flandre journeyed to another world in search of her sister, but instead, she found a much tinier Remilia. To differentiate them, she started calling this Remilia Big Sis, and she was determined to never lose her. She made her own body bigger with magic to become an unbeatable guard. However, it seems no matter how big and strong she becomes, some fates cannot be avoided... "...Big Sis?!"

"Not again..." Remilia is an extremely prideful vampire, but she is also whimsical and creative. With the magical knowledge she learned from Patchouli, she instructed her goblins to make a toy that replicates her voice. That's how she confused Flandre and snuck out of the mansion. However, the Remilia Guard cannot be shaken so easily. As soon as Guard Captain Flandre started searching for her, she found a clue: a sandal that Remilia had left behind. With the sandal dangling from her fingers, Flandre sat down on the beach and listened. Before long, she heard a voice from far out at sea. It was Remilia talking to her swim ring, Noble Heart. Flandre smirked as she whispered, "Found you, Big Sis."