Here's another sketch I did of Mary having a smoke break because I feel like she would be if she isn't drinking, which despite her death isn't actually a lot. Granted she isn't clean and still uses them as coping mechanisms but the effects of the buzz actually don't actually last that long for her so she mostly just does it to get some temporary relief from the constant hangover. However she is more likely to smoke to "take some of the edge off." She thinks she doesn't have a problem but often uses these substances as an excuse to justify being a huge jerk which she doesn't feel bad about because to her, she's just "being honest."
I think most people would probably write her off on her blunt behavior which is reasonable because she is in hell for a reason but there's also more to her that meets the rude surface layer that most don't bother to look for after an initial first impression.
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