Kisuke's former base in the Soul Society was located in the West Rukongai. Therefore, Aizen had known from the start that Ichigo and the others would appear in the West Rukongai.
The gate leading from the West Rukongai into the Seireitei was the White Road Gate. So, Aizen's order to Gin was to prevent Ichigo and the others from passing through the White Road Gate, thereby forcing them to seek out Shiba Kukaku and enter the Seireitei via the Flower Crane Cannon.
This way, when Ichigo and the others entered the Seireitei, they would likely be scattered. Consequently, the Gotei 13 would also have to disperse their forces to search for and capture Ichigo and his companions.
Moreover, with the group scattered, it would require more manpower and time for the Gotei 13 to apprehend them. This would allow Aizen to take action while they were distracted.
…
The Next Day.
6th Division's Prison.
"Renji, what is it? Has my execution date been moved up?"
Rukia looked at Renji and the group of Onmitsukido's members behind him.
"No. It's just that there are only fourteen days left until the execution. So, I need to transfer you to the Senzaikyu, the Palace of Penitence."
Renji said with a somber expression.
"I see. Let's go, then."
Rukia cooperated actively.
Senzaikyu is a tall, white tower-like structure located on high ground south of the Gotei 13's barracks, in the center of the Seireitei. It was a place for imprisoning major criminals.
Very few were usually imprisoned in the Senzaikyu. Today, however, Rukia was escorted here by Renji and the Onmitsukido.
"Rukia, do you see? Through that window, you can see the Sokyoku."
Inside the Senzaikyu's cell, Renji looked at Rukia with a complicated expression.
"Those are the two execution tools that will be used for your sentence. You can see them through the window every day, to repent for the crimes you have committed. That's the origin of the name 'Senzaikyu'..."
Renji explained.
"Repentance, huh..."
Rukia murmured to herself.
At that moment, an Onmitsukido's member suddenly spoke up. "Lieutenant Abarai, thank you for leading the prisoner transfer. However, now that the task is complete, you should leave with us."
"Uh... Alright."
Renji said helplessly.
Renji had wanted to talk with Rukia a bit more, but it seemed there was no chance now.
But just as the Onmitsukido turned away, Renji quickly whispered into Rukia's ear, "Listen, Rukia. I have unconfirmed news. Yesterday, Ryoka invaded the Soul Society. There are five of them. I heard among them is a Shinigami with orange hair, wielding a katana as tall as he is."
Hearing Renji's words, Rukia's heart stirred, and a look of joy appeared on her face.
'Orange hair, a katana as tall as the wielder... It was very likely Ichigo.' Thinking this, Rukia couldn't help but feel overjoyed, but also worried about Ichigo's safety.
"Cough! Lieutenant Abarai, why aren't you leaving yet?"
The Onmitsukido's members had taken a couple of steps before noticing Renji hadn't followed. Turning back, they saw him still standing there.
"Oh! Coming, coming!"
Renji hurriedly responded and caught up with the Onmitsukido.
Senzaikyu Corridor.
Renji walked alone down the corridor.
'How long has it been since I last saw Rukia look that excited...?'
'However, the one who confronted them was Captain Ichimaru... That guy... I'm afraid... it's over...'
'Well... That's probably how it should be, right...?'
Renji walked, lost in thought.
At that moment, a voice suddenly reached him.
"Yo, Renji. Long time no see!"
Hearing this, Renji looked up to see Aizen walking towards him.
Renji was instantly surprised. "Captain Aizen?"
"Could I have a word with you?"
Aizen smiled warmly.
"Come to think of it, it seems we haven't spoken like this in a long time. Ever since you graduated, decades have passed without us having a proper conversation."
Aizen remarked somewhat nostalgically.
"Oh..."
Renji responded casually, but inwardly wondered why Aizen was seeking him out.
Although Aizen had invited Renji to join the 5th Division when he graduated, Renji, on Toshiro's advice, went directly to the 11th Division instead. Over the years, they hadn't had much contact, and their relationship wasn't particularly close.
So Renji truly didn't know why Aizen specifically wanted to talk to him.
"You're in the 6th Division now, right?"
Aizen asked.
"Uh, yes. Is there something you need from me?"
Renji asked, puzzled.
"Renji, your relationship with her... with Kuchiki Rukia... it's not ordinary, is it?"
Aizen asked with a smile.
"Mm... well... that..."
Renji hesitated, unsure how to answer.
"I know all about it," Aizen said, his expression implying understanding.
"That's right."
Seeing that Aizen knew about his relationship with Rukia, Renji admitted openly.
"Then I won't beat around the bush. From your perspective... does she truly deserve to be executed?"
A glint flashed in Aizen's eyes.
"!"
Hearing Aizen's words, Renji's heart instantly tightened.
"Uh... I don't quite understand what you mean..."
Renji's expression changed.
"Don't you find it suspicious?"
"Her charges are: transferring her powers to another without permission and losing them, and overstaying her mission duration."
"I've never heard of such charges warranting execution by Sokyoku!"
"Also, the order to immediately return and destroy the Gigai, the reduction of the reprieve period from thirty-five days to twenty-five days..."
"And then the Sokyoku being specifically used for the execution... No matter how you look at it, it's all very strange."
"I feel this entire matter, from beginning to end, is being manipulated by someone!"
Aizen said with a grave expression.
As Renji listened to Aizen's words, a chill rose from the depths of his heart.
"Wait! Captain Aizen, what exactly are you—"
Before Renji could finish asking, Aizen said with a somber expression, "Renji, I have a very bad feeling about this..."
"It's possible that I—"
"Attention, all Captains!"
"Attention, all Captains!"
"An emergency Captain's Meeting will be held immediately!"
"Repeating, all—"
Before Aizen could finish speaking, an announcement echoed throughout the Seireitei.
"Ah... Never mind. I shouldn't tell you this. I wouldn't want to implicate you."
Aizen sighed.
With that, Aizen turned and left to attend the emergency Captain's Meeting.