similar to 'besties for restie'
people who are close, but not best friends however, even though the people will probably be good friends for the rest of their lives, it just rhymes better this way...
A person that cheers you up when you're down, stays by your side when the world leaves you, and do stupid crazy things with you. This person is your crying shoulder, your diary, and your comfort room.
Someone you is not your boyfriend or girlfriend but someone who lifts you up. They are probably more then a friend, but less than a boyfriend or girlfriend.