Reiko is a complex character, and Parasyte is an even more complex series. While the series is complete, I was left with a lot to think about even after finishing it. This section is the result. Filled with my own answers to questions brought up in the series as well as my own opinions of various things, consider this section "extra reading".
Self Sacrifice - Was it a species trait, or an archetype?
Good or Evil? - It's a blurry line.
Comparisons - Similar characters in other series.