This is based on opinion. Please don't list it on a work's trope example list.
Tear Jerker / Spinnerette
Every time Mecha Maid's ALS is brought up, particularly when she reveals that it's progressing faster. On a related note, Mecha Maid revealing that, because of it, romance was never really a possibility for her.
When Tiger learns of a school shooting he is initially afraid his daughters got hurt, and when he is overjoyed they're safe they point out someone else lost their daughters that day.
This page, and Heather's many conflicting emotions—including "I'm sorry I walked away I'm sorry I hurt you", "I'm scared", and in the corner, a tiny, little, backwards "Maybe I love you too." Someone give the poor girl a hug.
A minor one, but Spinnerettes reaction to Mecha maid hitting her is genuinely quite sad. however it doesn't last long as Spinnerette soon realises mecha is under the hate plague
The death of White Heron.
When Glass learns that the breeding camps and experiments left Mecha Maid paralyzed, he seems honestly regretful about it, and has a Pet the Dog moment by leaving Mecha Maid alive and telling her to spend her remaining time with her loved ones.
After three pages of trying and failing to push Heather away out of guilt, Marilyn admits that she intended to commit suicide through fighting Glass, before finally and understandably breaking down sobbing in Heather's arms.
Adastrea murders Dr. Singh, the only one with a possible cure for ALS in the Spinny universe, pats herself on the back for it, and then proclaims "justice" for going out and trying to kill every other patient with ALS.
Thanks to Spinnerette, some luck, and Singh's cricket skills, he actually survived, but the fact that she tried is horrifying, especially since she had been a patient of his that was able to live normally for years after his treatment.
After all the time and effort spent trying to stop Adastrea at the stem cell treatment center, Marilyn does not see any improvement from the treatment. To twist the knife, she had told everyone that there was only a one in six chance of it working, but her loved ones were determined to be optimistic and hoped for improvement.
In Heather's hometown, we have Sarah Nicole Megan, doped up into an ultra-PC and 50s-family-values mindset to the point that she spreads it to the whole town to keep the place perfect, even taking doses to keep from having a 'relapse' into being the old her.