The chapter begins with Leon giving his report of the last mission with Abel, Esther and Tres, when the Cardinal Sforza walks into the room. Having woken up early, the Cardinal is anxious to see the travellers again. She tells Kate to arranged someone to come and pick them up.
Tres, Abel and Esther are traveling on Adrian sea aboard the Ariel towards Vatican. Abel is confunsed why they are traveling on a such a fine cruiser, but rushes off to the bathroom due to seasickness. Esther is left with Tres, who assures her once again that her coming along is not a trouble. He leaves her as he goes on a patrol.
Esther starts to feel homesick, realising finally that she is now really far away from home. She wipes her tears when an older gentleman offers her a hankerchief. Suddenly, the nun is hit by a small plane. The man reveals miniature plane belongs to him, and that he is testing it for the night's show. The man tells Esther that he has a child like her, with pale skin and blue eyes, but is currently sleeping. Abel shows up and is shocked to see the man and appears to scream vampire, but it turns out he meant "Professor."
The three talk with the Professor Wordsworth about a rumor of the Saint Siren: A mermaid that lures a ship into a certain doom with her song. The Professor comments how the mermaid's song could sound just like Angelina's before they all fall asleep. Esther manages to see pair of fangs poking from Angelina's lips. The only one who doesn't fall asleep is Tres, as he is a machine. Angelina lashes Tres with her blade and damages his arm even more, making it fall off.
While Tres is paying attention to his arm, Angelina disappears and Tres goes to find her. When he is suddenly pulled underwater and Angelina's true form is revealed as being a type of vampire known as "mermaids". Tres comments that he cannot drown and that he won't die, he will just break. Angelina then attemptes to destroy Tres, when someone shoots her arm. Abel appears and pulls Tres to the surface while leaving Angelina in water.Angelina soon recovers and this time pulls Abel down with her into the depths, inviting him to go look for the bullet he had shoot right through her. Abel politely declines but Angelina does not take no for an answer. As she drowns him, Abel is left with no other choice but use Crusnik, but hesitates knowing Esther will see him. Beofre he has to make that decision, both the vampire and himself are pulled up by a giant robot.Esther realizes this was the Professor's "child", the "Poseidon WWW". The robot stops working and falls down while still holding onto Angelina, who the priests take with them to Vatican.