When Kyu joined Suju, they took turn taking him in their rooms. Kyu did not have a real bed, he slept on korean matrass. When fans found out and would buy it for Kyu, SM bought him one. Kyu was grateful so he posed with the bed and posted it somewhere, so fans could see he got the bed.
Sungmin shared room with Hae, and Hae did not enjoyed him snoring all night long and woke up with pink all over his room. Being a baby, Hae ended up rooming with Teukie. Hae loves being a dongsaeng. He was awkward with Wookie, Kibum and Kyu at first, because they are younger than him, he did not like being a hyung.
I think when Kyu shared room with Minhae, maybe Kyu once in a while sleep on Min's bed, and being Sungmin he prabably let him. If you are not used to slerping on the matrass on the floor sometimes hurting your back. I read somewhere when they are room mates, one bed full of stuffed animals, so they shared one bed.
Kyu shared room with Wook before that, and Wookie did not like it since Kyu played starcraft till dawn. He could not sleep, he even broke Kyu's keyboard and hide it.
Being roommates for 7 years states something.They are close for sure.
I saw on youtube conversation between Hyuk and Teuk about Kyumin's fighting, because Kyu hang up when Min called him. Min cried. Teuk found it. So Kyu followed Min around the next day.
After the accident the maknae was so spoilt by his hyungs. And Kyu made fun of his hyungs a lot and got a way with it. Kyu is such a brat. But he loves all his hyung, he went straight to dorms from the hospital because he missed them. I dunno whether his parents let him.
I am sorry I could not fimd the link, now since my internet is slow.

I wanna know too!! :D if you find something could you send me it please~? thank youuu :))

I think you can go to heezica on tumblr, she has some (I mean a lot) kyumin facts and posts, she also put the sources of them ^^

At first Kyu shared bed with Ryeowook and Yesung, yhen he moved to his room with Sungmin, but I don't know if they ever shared the bed DD: but they spent a lot of time together D:

I don't have link for both even I read about KyuMin's fight so many times. But This video maybe will make you believe KyuMin is MORE REAL, like it did to me :DDD
http://www.youtube.com/watch?v=gclCIDZj8NI

you can find a lot of kyumin facts in here
http://heezica.tumblr.com/post/26009534238

i've seen so many articles and watched so many videos, i've forgotten where i saw or heard which.... but i remember some information like kyumin having two bed and putting their thing on one and sleep together on the other when they're too tired... and then about that fight... is it that one when kyuhyun didn't answer sungmin's call, and sungmin cried???

it's sad but most of the old kyumin videos were deleted :(
but it's true, i ship kyumin for 4.5 years

I can't confirm how credible this is, but you can always do some extra searching. According to this source, Kyuhyun and Sungmin were on Sukira 070110 and they spoke about how Kyuhyun had to share a bed with Sungmin when he didn't have a bed.

http://sujubias.wordpress.com/2010/09/24/kyuhyun-doesn%E2%80%99t-have-a-bed-he-shares-one-with-sungmin/

I was watched video where eunteuk talking about kyumin fight in youtube, i'll see if i can find that lonk for you..

As for sharing bed, i'm not really sure bout that.. I even not really sure that min is really one of some members who welcoming kyu openly at first.