Romances these days are not for girls anymore, particularly in manga. These days, romance can also be found in shonen manga. Of course, it's hard to differentiate different shonen manga - it really depends on taste. I am keeping with multiple good shonen romance mangas that I think many will enjoy.
For people who can relate to gamers and those who think that reality stinks, and also want some supernatural themes mixed in, I recommend the World God Only Knows (Kami nomi zo shiru sekai), by Wakaki Tamiki. It tells of a gaming nerd named Keima who is known as the Capturing God for his prowess in dating sim games, the ability to 'conquer' any of them, and his hatred of reality, especially '3D girls'. He is roped into a contract by a cute devil to help expel evil spirits that reside in the hearts of girls. The best way to expel the evil spirits, of course, is to get the girl to fall in love with them. It's unique, has an interest and diverse cast of characters, and there's also a good mix of comedy to keep things interesting.
Some might want a good shonen romance manga that incorporates more realistic themes. In that case, there's two series that I would recommend: Kimi no Iru Machi, by Seo Kouji, and GE - Good Ending, by Sasuga Kei. The two series are relatively similar, save the setting. Kimi no Iru Machi focuses on a countryside boy named Haruto Kirishima, whose peaceful life suddenly gets disrupted by a cheerful girl from Tokyo moving in to his home, despite all his protests. GE is about a boy named Utsumi who consults with a girl named Yuki Kurokawa to win the heart of the tennis club's captain. These are their basic premises, but the story diverges from there. Both are relatively realistic, and there's again a good deal of comedy mixed in. They make for very interesting reads.
And then there are the shonen romance mangas that are, well, ecchi, to say the least. But these mangas have their own charm, and often involve slapstick comedy into them. Two I would recommend would be Mahou Sensei Negima!, by Ken Akamatsu, and To-LOVE-Ru, by Saki Hasemi and Kentaro Yabuki. Mahou Sensei Negima! is about a boy wizard from Wales who gets assigned to teach at an all-girl's school in Japan. It's hilarious, sweet, and lovable at the same time. The genre will shift toward action later on in the manga, but there's still a good amount of romance in the series. To-LOVE-ru focuses on an ordinary high school boy who suddenly has to shelter a lovely alien princess. One who loves making literally out-of-the-world gadgets, has insane strength, about heaven-knows-how-many suitors after her, and said ordinary high school boy is now her chosen fiance. Wacky hi-jinks are the norm in this series, as well as a lot of torn clothing. Nonetheless, there are scenes that are still touching, enough to qualify as a romance manga.
These are just some of the more popular mangas. Others might have different tastes, but these happen to be my favorite. I hope that this has been very informative in helping you to choose a good shonen romance manga.