If you liked the Rec anime, the Anime-Planet community thinks you'd like:
Art college: cradle of romance, home of bittersweet moments. Takemoto is struggling to find his direction in life, while his roommates Morita and Mayama are moving confidently - or recklessly - towards their goals. Enter Hagu-chan, the childlike and beautiful prodigy whom everyone admires; and thus the love triangles begin. Together, the trio explore the pain of first love, the trials of romantic conflict, and our loyalty to those annoying people who happen to be our closest friends.
Honey and Clover is one of the best relationship drama anime around. If you liked REC's short take on young-adult crisis of love and life, you should like Honey and Clover's as well.
Rec is way more childish and less dramatic then Honey and Clover, but both are very subtle in showing the topic of love. Both deal with relationship between adults , and therefore include topics like job or money (as an addition to romance of course)
And lastly - both are concerned with artistic problems. Whether it is art school (in H&C) or being seiyu (REC)
Keitaro Urashima is somewhat of a failure. In order to fulfill a promise he made to a girl fifteen years ago, he has tried time and again to get into Tokyo U but has never managed to pass the exam. However, fate smiles upon him and he ends up working for his aunt, managing an all-girls dorm! Living with the feral Kaolla, the timid Shinobu, the sake-loving Mitsune, the blade mistress Motoko and the punch-happy Naru, can Keitaro keep his focus and keep his promise? And will he ever end up meeting that girl from his past?
Both Rec and Love Hina deal with a protagonist who is a failure when it comes to love. Love Hina's main character is a student who keeps failing to get into the college of his choice, who wants to reunite with a childhood love. REC's main character is a business man who constantly gets shut down by women, especially a specific woman he likes from work. Both protagonists meet a random woman who begins to change their luck, and both anime are excellent romantic comedies.
both animes involve people who are getting to live under the same roof as romance starts to grow between them
Sawamura Seiji is the most notorious delinquent at his high school -- always getting into fights and causing problems, leaving him single and unlucky with the ladies. After another long day of rejection, Seiji discovers that the love of his life might have finally appeared, but in the unlikeliest of places... his right hand?! Now, in addition to dealing with daily fights and the gossip of his classmates, Seiji must handle a new problem of embarassing proportions: Kasugano Midori, a pretty young girl in place of his hand, who happens to have fallen in love with him!
Both of the series deal with a very sudden relationship of two people, which really lacks of what you would expect of a normal start of a relationship, and a person unable to realise her/his true feelings. Moreover, both of these are heartwarming and rather amusing stories.
A man and a woman (Unrelated) living together? Check. But where Rec has the main female's home burned down, Midori Days is a bit more... unusual. Even so, it means some endearing and adorable interactions and budding romance. Some rough spots in the relationships means that the make up would be that much more smile-inducing. And a good dosage of comedy inbetween the romance and drama that occur.
Yamato Akitsuki has recently moved to Tokyo, and in order to maintain his less than wealthy lifestyle, he currently works at his aunt's bathhouse. While walking by the school one evening he sees a girl by the name of Suzuka practicing the high jump, and is instantly in love. Even better is the realization that Suzuka lives next door! Determined to prove himself worthy of her affections, Yamato decides to join the school's track team and show her what he’s got, but things won’t be so easy; for Suzuka has a love interest of her own, and it isn’t Yamato...
Suzuka and Rec are not your every day romantic comedy. In both you'll find your good laughs and the sweet romance, but you'll also find people will dreams and pasts - people that think seriously about their relations. Yet the overall tone of both anime doesn't turn into a melodramatic soap.
both animes involve people who got to live together/near each other and as they continue their lives together there is also some romance
Ryuuji Takasu has an eventful life: his classmates think he's a delinquent due to his 'killer' eyes; his crush Minori seems ever out of reach; and he’s just had an unfortunate encounter with 'palm-sized Taiga' – a feisty and dainty wench in his class. With different cleaning habits and tempers, the two clash like night and day; that is, except for the fact that Taiga and Ryuuji have crushes on the other's good friend! With school rumors abounding, the duo must now work together to play matchmaker for each other. Who will end up with their true love?
While this wasn't exactly the first thing that came to mind, this is the best recommendation I could possibly make for Toradora! and REC. Both anime are Romantic Comedies of the best sort. They have actually funny humor, spend time developing the characters and conclude in a way that make the characters seem like -you know- actually thinking, responsible young adults, rather than going in head first into some feeble relationship. If you enjoyed one of these shows, do-not-hesitate to check the other out!
If you enjoyed Toradora! or Rec, you may want to watch the other. Even though the storylines, settings etc are quite different, they are similar in that the protagonists take thier relationships in a serious, mature manner while maintaining a lightly comedic atmosphere. In both anime the protagonists are often living/staying over under the same roof. Also, unlike some other comedy-romance anime, the male protagonists do not recklessly chase one girl after the other and there is next to no 'genuine' ecchi, though moreso in Toradora! than Rec.