The OPM anime is known for being relatively faithful to the manga. It keeps the main events and character developments intact. Though there could be some small changes for visual or pacing reasons, it doesn't significantly deviate from the manga's storyline.
Crossroad Games and Comics are known for their creativity. They might have innovative gameplay mechanics in the games or compelling narrative arcs in the comics. The visuals could be either realistic or highly stylized depending on the theme.
Perhaps the stethoscope is there to show that the animal has a caring side and wants to help others. Or it's a symbol of some kind of adventure or mystery related to health in the cartoon world.
You might try looking on some popular comic websites or online marketplaces. Sometimes, specific comic forums or fan communities could also have leads.