As far as I can see, the diaper_bulge tag is currently used in the following ways:
- An used diaper, sagging or bulging due its own weight. post #3898442 (There is already sagging_diaper for this, and hyper_* tags for when the diaper is used too much)
- A diaper getting "tented" due to an erection. post #3444336 (we could just use tenting, diaper_tent, erection_under_clothing, penis_outline, bulge)
- A diaper_under_clothing with its outline visible through the clothing. (If its possbile to tell there is a diaper_under_clothing, then either the diaper is partially visible (exposed_diaper post #3507670), or there is a noticeable diaper_outline post #3291093)
Diaper_outline isn't a tag that is currently used, I guess diaper_under_clothing already fits this purpose?
With that in mind, my first idea was to alias diaper_bulge to bulge, just like underwear_bulge is. But this may lead to some mistags since diaper_bulge can have other meanings, and the "bulge" tag doesn't clarify what its purpose is at a first glance.
My second thought was to alias diaper_bulge to diaper_outline or alias diaper_bulge to diaper_under_clothing. Since they have a clear purpose(like underwear_outline), it may be easier to clean up said mistags that may occur. And I feel it matches what I assume is the most common interpretation of "diaper_bulge", which is when the bulge of a diaper is visible under clothing.