I haven't noticed an attractive female wear diapers since I was in my tweens, at a day camp for the disabled (as I am), and saw a girl in a swimsuit and thick footed tights (probably sweater tights, to protect her feet). She had a definite diaper bulge, and I did fantasize about her whole ensemble. Quite the mixing of fetishes! But it wasn't for fetishism. It was just what she needed.
Nowadays I fantasize about a girl I knew in the mid-00s. She wore a mask for medical purposes (lung transplant, both before and after). She also wore it in some of her deviantART modeling. It was a fetish for her, even though it was medically necessary as well.
Another fetish she modeled is being tied up. This isn't something that excites me per se. But it has gotten me thinking about my other fetish, which is young women in footed pajamas. Some ABDL suppliers that make those have add-ons, like a rear zipper, and thumbless mittens. There's something very erotic about this for me. I do fantasize about seeing my old friend wearing footed, mitted, rear-closed pajamas, and her big black silicone cartridge mask strapped tightly on her mouth.
In this instance, if she went to bed this way, she'd need a diaper, incase I slept too deeply to be woken in the middle of the night to help unzip her for the bathroom.