Question about tramp stamp, lower back tattoo.?

Ok so I have decided to change the tattoo I have on my lower back. I currently have a small light pink one that I think is easy to cover up with a new one over the top. The problem is I despairly need some ideas maybe even a link of the most desired, y, tattoo that will absolutely wow my boyfriend. This has to be good. I want to make sure it's something i'd love before deciding. Can you suggest anything? I don't want something everyone else has. Remember y is the key word and it's for my lower back and will be a cover up. What do you think?