Yes, a diaper of this size may seem impractical, embarassing, and out of place in a lab, but somehow the current Royal Scientist has created a large batch of them. Why? So she can watch her favorite animes without the need for silly bathroom breaks. After all, her lab's the only place in the underground that her cameras won't capture, so she can go nuts with nobody knowing.
Not to mention that baby bottles are much cleaner than regular cups, and easier to clean afterwards, since unlike her preffered brand of instant ramen, Alphys' drinks of choice cause quite a bit of a mess if left unattended.
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I've practiced doing better looking traditional art lately; mostly by copying other drawings. I thought it was about time to draw Alphys again, and I'd say that I didn't do half bad.

Alphys is from Undertale and I don't own her.

Messy Version: https://www.furaffinity.net/view/36564336/