Chapter 003 is the third chapter in Volume 1 of the Manga Series.
Lucia and Hanon are in the bath, when Lucia shows off the new ring she made. Lucia gives the other one to Hanon as a symbol of their friendship. Lucia decides to make one for the new exchange student too.
The girls get out of the bath tub. Then Hanon starts talking about the new girl and her lack of communication skills when Lucia decides that she will become friends with Rina.
Hanon then leaves the room, while Nikora and Hippo come in. Nikora talks to Lucia about the new disasters happening in the oceans. Hippo warns Lucia about the possibilty that the other mermaids could be captured, when Lucia's towel (that was covering her body) accidently drops to the floor. Lucia exclaims that she will save the other princesses and defeat the enemies.
Lucia is walking down the stairs when she sees Tarou playing the piano and Hanon standing right next to him. Lucia then goes outside and sees (to her shock) Kaito and Rina together. Lucia thinks their kissing due to the angle she is standing at and drops the friendship ring. She misunderstands the situation and looks in horror. Rina starts proclaiming that Kaito is "evil" and a "devil" leaving him confused and a bit annoyed. Rina walks away, while Kaito picks up the ring that was lying on the ground.
Hanon and Lucia are sitting on some stairs, while Lucia is looking sadly at the ground. Hanon suggests that is might of been a misunderstanding and shows her the new concert tickets that Taro gave her.
Meanwhile at Panthalassa Kingdom, Gaito is standing with Izuru examining the Arctic Ocean Mermaid he captured. Gaito starts planning on capturing the other mermaids, when Yuri comes through the door. Yuri laughs at Eril and Izuru's defeat from the mermaids. Gaito inspects the other mermaid he captured, while laughing at his future plans of taking over the oceans.
Rina comments about Kaito's rich dead parents and the nice house that he lives in. Rina suddenly grabs Kaito by his shirt and realises that he ressembles Gaito. She drops him in alarm and remains shocked. Kaito says that he won't forgive her if she keeps making bad comments about his family especially his dad.
Out of no where, Lucia appears and suggests that she will sew on the broken button on Kaito's shirt. Kaito notices the ring that Lucia is wearing is similar to the one he picked up from the floor previously. He invites her into his room, while he goes to have a shower. Lucia starts sewing the button when she accidently pricks herself. Kaito appears and starts sucking the blood from her finger.
Kaito gives her his parents' Cd and the friendship ring back. Lucia wonders how he got it, when Kaito winks at her and states that him and Rina aren't in any kind of relationship. Kaito starts to think about the pink mermaid, just as Rina is standing outside his room and overhears them.
Hanon, Lucia and Kaito go to see the music performance that played some of the Domoto's old music songs. When they leave, Lucia notices Rina and tells her to go check out the performance. Kaito and Rina look at each other angrily. Not taking any notice, Lucia gives Rina the friendship ring. Rina takes it and walks away.
Rina starts thinking about the time, when Gaito and Yuri captured the Arctic Ocean mermaid. She sadly clutches the ring. Yuri starts playing a song (that will attract the mermaids) on the piano. This immmediately has an effect on Rina, Lucia and Hanon. Lucia and Hanon transform, meanwhile Kaito hears a famillar voice. Rina is surrounded by some people in the crowds while Kaito saves her. Rina is now able to transform and she reveals her true form. The girls start singing and they defeat Yuri.
The next morning, Lucia and Hanon are late to school so they run quickly out the hotel. They notice Rina and Kaito so they stop running. Then they hear the school bell, so the group rush to class. Lucia notices that Rina is wearing the ring so she smiles.