The xx is yet another indie/pop group that specializes in great lyrics and mellow beats. You can't really dislike them - maybe you don't love them, but who could hate them?
It took me a while to decide what song in specific to recommend. They only have two albums but pretty much all of their songs are amazing. In the end, I went with the first song I heard by them - "Night Time". It's got a really understated pop-y beat that you'll catch yourself humming during the day. (Be careful with that, it could get really awkward.)
Most of their songs make use of the other male vocal with no obvious "lead" singer, but this one is all one person. It's what separates it from the rest of their songs.
The lyrics are short, sweet, and to-the-point ("Should release but just tighten my grip"; "Hold my words, keep us together") like they usually are. They have a very refreshing, minimalistic approach to indie pop.
Are you curious yet? Wanna see if you like it? I'll help - all you have to do is click play.