its just after you meet mark, for anyone looking at this in the future, the number randomizes so its not possible to share it. though i can share the exact location
1. start prologue (first time new game scene)
2. continue until you can refuse to be a girl with "think about the situation"
then the "bloody hell no I want to be a man!" option
3. click the only blue option until you see the pick vial, should be on the same screen as mark
4. the number will be randomized but is the last bit of text before the syringe picture
