The underworld is the resting place of souls, so it must have a way to preserve souls from perishment.
With this in mind, Senga immediately prepared to activate the Devil Fruit ability) she had just acquired.
Just then, Brook's voice rang in Senga's mind.
"Senga, after losing the Revive-Revive Fruit), it seems my soul can no longer return to my body. Perhaps I should just leave now."
"What?"
Senga frowned. Wasn't Brook quite eager to explore the outside world before? Why has he suddenly changed his mind?
Brook said calmly,
"Once I was freed from that skeleton, I suddenly felt a sense of liberation. I had lived long enough and wanted to go there to reunite with my companions. What a long time it had been!"
Upon hearing Brook's words, Senga fell silent.
He wondered if it was even worth it to bring Brook back to life; did Brook really want to die?
Sometimes, a long life is not a good thing; without someone you care about by your side, it's more like torture.
Moreover, Brook lived in a state that was neither human nor ghost.
But if Brook's soul were simply allowed to return to the underworld, wouldn't that mean Brook died by his own hand? What would have been the point of everything he had done before?
Furthermore, Brook is not without ties in this world; he still has Laboon, a whale who has been waiting for him for nearly fifty years, at Reverse Mountain!
So Brook can't die yet, at least not by my hand.
Thinking of this, Senga's left eye began to emit a pale blue chill, which was fundamentally different from Aokiji's chill; it came from the underworld.
"Brook, you still have an unfulfilled promise. Carry that promise with you and continue living!"
The Underworld Cold Air surged towards Senga's hand, which was grasping Brook's soul, and enveloped it.
Without powerful Haki cultivation or special abilities, one would be instantly frozen upon encountering the Underworld Cold Air, which could even damage one's soul.
However, Senga obviously wouldn't let that happen. The Underworld Cold Air can harm the soul, but it can also nourish it.
After acquiring the Revive-Revive Fruit), with the aid of the Rinnegan, he could easily switch between the two states of Underworld Cold Air.
After Brook's soul was enveloped by this Underworld Cold Air, he couldn't help but let out a few comfortable groans.
However, before he could enjoy it for long, Senga grabbed him and stuffed him back into the skeleton's body.
After his soul returned, Brook's brow twitched, and he said hesitantly,
"Am I... alive again?"
"Yes, you're alive again."
Senga checked for him and then gave him some instructions.
"I have infused your soul with the Underworld Cold Air. From now on, you can use its power. But remember, once you've used it all, your soul will leave your body and return to the underworld."
Senga was giving Brook a choice: to decide his own life or death.
Brook quickly understood what Senga meant. He felt conflicted and didn't know what to say for a moment.
Seeing Brook standing there in Senga assumed he was still contemplating the question of life or death, so she spoke to him.
"Stop thinking about it. If you still want to reunite with your companions, you can use all the Underworld Cold Air now. Don't worry, you won't feel any pain during the process."
Brook nodded, still feeling grateful to Senga.
Brook's previous Rumbar Pirates, were the type of "adventurers" who did only good deeds.
Just look at their slogans and you'll know.
"To make a crying child smile through their tears."
However, such pirate crews are ultimately a minority. Brook also witnessed the behavior of some of his fellow pirates on his journey; they would steal whatever they saw, which is the survival strategy of most pirates.
Although he had never done such a thing, he was already used to it.
He knew that with Senga's strength, there was nothing he could do if someone tried to forcibly take the Revive-Revive Fruit from him.
But Senga didn't. He went to Moria's place to retrieve his shadow and even managed to save his own life.
Brook, on the contrary, felt that he owed Senga a favor, which made him feel a little embarrassed.
Senga had no idea what Brook was thinking; if she did, she'd probably burst out laughing.
The Revive-Revive Fruit) is very powerful, and I even feel like I got a good deal, so why would I think Brook owes me something?
It's no wonder this is the Pirate World; some unspoken rules have become deeply ingrained.
Senga is now thinking that it's not good to leave Brook here alone. It would be better to let him go see Laboon the whale, so that Laboon won't keep crashing into the Red Line Continent and getting hurt all the time.
Thinking of this, Senga had an idea. He said to Brook,
Do you remember Laboon?
"Laboon!?"
Brook never expected to hear Laboon's name from this Senga.
He had no idea how many years it had been since he'd heard that name; how could he have forgotten Laboon?
Although Laboon is a whale, he had long regarded Laboon as his partner, the kind of partner he would entrust his life to.
Brook, disregarding all politeness, excitedly grabbed Senga's shoulders and shouted,
"How would Senga know about Laboon? Have you seen it before? Where is it now? Is it alright?"
A barrage of questions came out of Brook's mouth, revealing just how urgent he was.
Senga understood Brook's loss of composure. Laboon the whale was a classic storyline in the early stages of One Piece, and it genuinely moved him at the time.
Everything Has a Spirit, and sometimes the feelings between people are not as genuine as those between a whale.
Senga has already fulfilled many dreams in the Pirate World; this time, let's help these two "fools" fulfill their dreams too.
He looked into Brook's empty eye sockets and said,
"It's still waiting for you in the same place, it hasn't left for a moment. Would you like to go see it?"
"When..."
Brook almost blurted out "Of course," but then he remembered his promise to Laboon.
Their agreement wasn't just about meeting; the prerequisite for meeting was that the Rumbar Pirates would circumnavigate the world.
However, after leaving Laboon, they all unfortunately contracted the plague. In the end, only Brook survived thanks to the power of the Revive-Revive Fruit), and he stayed alone on the empty pirate ship.
This vigil has lasted for nearly fifty years!
Brook was eager to see Laboon immediately; he was practically obsessed with it.
But the agreement was not yet fulfilled. For Brook, an agreement was a man's promise, which could never be broken.
Brook was thus caught in a dilemma between his promise and his companions.