Ikkaku didn't mean anything with the question. He was just curious.
"Why d'ya wear socks?" Ikkaku hated socks, thinking they imprisoned his feet and didn't think they allowed his feet to breathe. He was seemingly the only one in Seireitei, something that confused him, but Yumichika usually understood what he meant, or at least tried to.
Yumichika's (uncharacteristic) grunt of an answer was impossible to make out, so Ikkaku asked him again, slowing down so that he walked beside Yumichika for once.
"… feet", Yumichika mumbled, seemingly embarrassed with his eyes on the ground. The extreme thought of Yumichika being embarrassed was very unfamiliar to even Ikkaku, his best friend of a century.
"What?" he asked again, not being able to stop pushing something that elicited such a strange reaction from Yumichika.
"My feet", Yumichika mumbled a bit louder, more annoyed now then embarrassed. "I don't like them." The thought of Yumichika being embarrassed by something was ridiculous, but the thought of him ashamed of his own appearance was just… utterly laughable.
"Did I just hear that?!" Ikkaku said, trying not to laugh. "Yumichika, yer seriously… ya don't like yer appearance? Ever since I met ya, ya kept praising your looks, they were your pride, along with yer fighting ability", he somewhat scolded. "But-"
"Enough!" Yumichika cut him off, looking up again with a flushed face and furious violet eyes. "Don't push it", he threatened and Ikkaku knew better than to make him a very mad Yumichika.
They left the subject, and kept patrolling the streets in quiet. Ikkaku found himself looking at his toes again, causing him to think about what Yumichika had said again. So he stopped and turned.
"I just can't forget about it", he started, but was quickly interrupted by a blade by his throat.
"Don't. Push. It." Ikkaku was not a man to be threatened by a sword, so he draw Houzukimaru and a battle began.
An hour later, the battle with Ikkaku as the winner was over. They were both sweating, so when Ikkaku suggested they should head to the hot springs Yumichika agreed and joined him. Of course, he was unaware that the usually not very thoughtful Ikkaku actually had a plan.
When they were in the locker room, Yumichika removed his shoes, and then his socks…
"AHA!" Ikkaku yelled when the strip was done and quickly took a hold of Yumichika's left ankle, yanking the foot up.
"Aow! Ikkaku, let go!" Yumichika yelled, trying to stay standing on just one foot as his other was examined by Ikkaku.
After a long, quiet, study Ikkaku talked. "I don't get it, I thought you had warts or something…"
"I would never-"
"But it's just a normal foot." Yumichika managed to free his foot at least when Ikkaku's grip weakened.
"Exactly…" he muttered and started to walk to the hot spring itself. "It doesn't add up. Why would one as beautiful as I have such mediocre feet?"
Ikkaku didn't mean anything with the question. He was just curious.
"Then why didn't ya say so from the beginning? Ya know ya can't keep anything from me." He too walked towards the spring. Yumichika decided to let it go. After all, what could one with as beautiful feet as Ikkaku know about Yumichika with his mediocre ones?