Kokoro

Kokoro (ココロ) is the main conductor of the Sea Train, Puffing Tom, at the station just outside of Water Seven. She has a granddaughter named Chimney, who accompanies her everywhere. Like some of the other characters of One Piece, Kokoro has a unique laugh, she starts it with a "Nga" (i.e. Nga ga ga ga ga!)

Appearance
Her facial features make it look as if she is perpetually smiling regardless of her actual emotions. Her body shape, along with her strange smile, makes her look like a frog. (She is, in fact, an icefish mermaid, though resembles more of a dugong in terms of appearance and shape.) "Kokoro" translates from Japanese as heart, in the emotional sense, or emotion.

Personnality
Kokoro is a heavy drinker, and speaks with a mild speech impediment that gives her dialogue a distinctive ring. While she does have a temper she tends to keep it under control and seems to remind happy no matter what events unfold remaining strangely relaxed and calm. She takes a liking to Luffy and eventually refers to him as the Pirate King. She is very curious about him because the events at Enies Lobby became very intereasting. She came to the conclusion if Tom were still alive he would have helped him just as he had helped Gold Roger.

Early Life
She left Fishman Island to support Tom and met her human husband in Water 7. Together they had a son who was 1/2 Mermaid.

Tom's Secretary
Kokoro became the "lovely" secretary of Tom, and a matronly figure to his two apprentices, Iceburg and Franky.

When Tom was taken to trial in 1522, Kokoro was watching the whole thing. After Tom was given a 12 year sentence to build the Sea Train, Tom laughed about being given a chance, but Kokoro had been scared by Tom's brush with deathand did not appreciate him laughing about it. She even later told Iceburg that he has to get over with Franky.

During 12 years, Kokoro visited Enies Lobby with Tom. After 12 years was done, the Judge; having to see Tom's work decided to pardon him but the Judicary ship exploded. Before that Franky was on his way out but Kokoro threw him the pants and demand him to wear it.

When Tom was captured by Spandam and his agents, Iceburg, Franky, Kokoro and Yokozuna was brought to trial. However Tom sacrifice himself to free the others by saying he was proud to help Gol D. Roger and wounded Spandam. After Tom was tranqulized, the Judge decided to take only Tom and free his workers. Kokoro emotionally hugged Franky and Iceburg as she explained that convicts never come back form Enies Lobby. Furious, Franky attacked Spandam and broke his face. After Franky was runned over by a Sea Train, Kokoro annouced that Franky was dead and she then became Iceburg's drinking buddy.

After this, she became an former secretary, taking up a new job as a stationmaster of the Sea Train Blue Station. During 8 years, Kokoro grew with age, becoming an heavy drinker, bitter about losing Tom and angry towards the World Government. Later, her son left Chimney and Gonbe under her care.

Water 7
8 Years later, the Straw Hat Pirates arrived at the Sea Train station, they met Chimney, Gonbe and a drunked Kokoro. Kokoro told them about the Sea Train and how they work, then she offers them the Sea Train route to Pucci, San Paldo or St. Popler but Nami told her that they must only follow the Log Pose. Kokoro told them that Iceburg should be able to help them repair the ship, she wrote a note and a bad map drawing to Water 7 which later annoys Nami.