Oh~

HAHAHAA XD That's fine~! *puts on a teacher's hat and gets the pointer stick*

It's a parody of the manga characters being a boyband named "Ayakashi" and they're performing their debut song A.YA.KA.SHI at N・K Hall

This was the bonus section that the mangaka drew for New Years (since Arashi did perform A.RA.SHI at NHK Hall) XD

As far as I know, mangakas usually make allusions or parodies to Arashi, there are times where they just mention them.

But in terms of comics with Arashi members, you're thinking of doujinshis and there's a community on LJ that shares the scans of these doujins X3

oOoooOOo.. :D *nod3x*
i get it now~ *nod3x* thank you~~ <3 <3 <3 *bow* >///<

yes, i also join with some communities that shares the scans. XD
some of the doujins are very funny ^o^~
hahahahhaa~