The first manga is about a girl with pony tails. She's living in a dorm with guys. I think the dorms are ranked like A dorm and S dorm. A guy from another dorm likes to call her tails because of her hair. It's a romance, comedy. Also, there are various types of guys in the dorm. (This is all I cam remember.)

Next I'm looking for a type of manga. Like a comedy, romance, supernatural type of manga. Any suggestions?

is it shoujo? if it is it might be S.L.H - Stray Love Hearts! but then again, I dont recall anyone calling her tails...

anyway for your second.. I recommand something from the author of S.L.H - Stray Love Hearts!
Barajou no Kiss it's harem mind you..
Densha Otoko - Net Hatsu, Kakueki Teisha no Love Story is a light comedy romance.. no supernatural
Kanata Kara
7 Senchi!
1/2 prince
Absolute Witch
Hanatsuki Hime

http://www.mangaupdates.com/showtopic.php?tid=31662&h l=comedy%20romance%20fantasy
this post might have more for your second requirment

comedy, romance, supernatural - Orange Marmalade and Kami-sama Hajimemashita

No clue what you're talking about for the manga you are looking for, but for some reason I'm reminded of
Bishoujo Senshi Sailormoon (If I remember correctly he calls her tails, then changes to buns or something.) but I know that isn't it since it's not in a dorm.

As for suggestions on those genres in a manga there -
Barairo My Honey
Birthday Presents
Fruits Basket
Full Moon Joker
Oretama
Soryanaize Darling
Tsuiteru Kanojo (ENJOUJI Maki)
I second Kami-sama Hajimemashita

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Sorry I couldn't help for our first request!

Second request:
Gakuen Alice
Crazy Girl Shin Bia
Ghost Hunt
Merupuri
Shounen Dolls
D.Gray-man - Ah, no romance.
Code: Breaker - No romance. :/
Melo Holic - one really extreme and shocking part though.

No supernatural, just some really nice comedy and romance:
Love Com
Tokyo Crazy Paradise
Skip Beat!

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