This is an exert from this DMMTV interview on twitter

This interview is with the character designer, Tani Shiroi, and the director, Koide Takushi.

Q: Lara and the other mermaids have ears shaped like gills. If you look from afar at their whole body, they seem similar to humans, but when you look closely you can see they have a different design. How did you determine this?

Tani: I wondered if it was okay for a mermaid who wanted to become human to have the same appearance as a human, so I put a lot of effort into the design.

Koide: There are other subtle differences between how the mermaid characters and the human characters are drawn. The way their eyes and hair are drawn are actually slightly different also.

Tani: While I said I wanted to broaden the appeal (of this work), I also had a voice in my head saying "just do it". Okamoto Tarou (A famous Japanese artist) is known for saying, "art shouldn't be comfortable," so I wanted to add something to this work that would make people uncomfortable when they saw it. So I decided to try to design them with the idea that it would stand out when you really looked closely.

Something something about a red haired girl who became human via magic from a mysterious entity with ulterior motives and their stoic, dark haired partner who saves them from a watery grave and somehow subvert their fate to vanish if they confess their love…

The sister's and younger Lara voice actors got to come in and record for the first time in a while. They said they gave off a healing atmosphere.

And then they recorded the serious scenes. Lisa being trapped, Grace laughing, and Luna being shocked at Lara being gone. It says their acting was really good.

For Kouta's voice actor, he said he felt like his character was looking for every single chance he could to say "Lisa-sama" and Mari's voice actor said it seemed like it would be a bit of a tongue twister to say the two "sa"s in Lisa-sama so much. It says "Lisa-sama Lover" on top of him.

One day, she received a warm can of hot chocolate from the girl. Since Lara felt her heart melt the first time she tasted that sweetness, later, she also gave a piping hot can of hot chocolate to the girl.

Because that was the greatest sweetness that Lara had ever experienced in this world. Because she felt like it would become a sign if great affection.

Lara came to love sweet things and started working at a cake shop after saying something outrageous like, "I'll die for cake!"