I wouldn't really suggest using perfume because if you accidentally apply too much or it's too strong or someone's really sensitive, you might set off some allergies.
That said, try axe shower gel. I hate Axe usually but my best friend uses it and it isn't overpowering or anything. It's actually really subtle but the scent is just strong enough to stick for the day. I don't know if that actually goes with the character but it smells like dude to me. None of my guy friends are really into scents and stuff outside of body wash and shampoo, and even then they don't really care.
For girl Ciel, that dress reminds me of Bath and Body Work's Pink Chiffon scent, or at least its packaging. It's sweet and floral. The body cream that I have describes it as, "an ultra-feminine blend of sparkling red pear, vanilla orchid, and whipped chiffon musk." Another thing you can try is the Body Shop's Love Etc... scent. I love the perfume but the body butter is also really amazing. My boyfriend says it smells like earl gray tea but the site describes it as, "a sensuous blend of Egyptian jasmine with warm, radiant notes of vanilla and sandalwood." I don't think either of those scents smell particularly mature, especially Pink Chiffon.
What's this for? It's a wig.
What's it for? To disguise yourself from yourself.