The second youngest of Jack's Alter Egos, Dr. Schneeplestein is as optimistic, energetic and confident as his creator, though more prideful at times. He cares deeply for the few friends he has, the closest of which seem to be Jack himself and Chase Brody, and pours all of the knowledge he has into treating them and teaching the viewers, even if some of his knowledge is flawed.
Only fragments are known of his backstory and personal life: His birthday is September 15, 2016. He owns a Twitter account, Jack's song "All The Way" is constantly stuck in his head, and he has a possible crush on Barbie (though he's willing to flirt with the viewer on occasion). His work phone number is 1890-485-6239-5946-4659-8321, but it's rumored that he has no proper medical license. Although he mentions a wife and children, it's implied that they don't have a healthy relationship; he bitterly remarks that his wife would rather stay with her tennis instructor, Rick, and that he "doesn't have anybody who loves him."
Schneep is highly independent and adaptable. He prefers not to use instructions or conventional tools and works best when he can explain what he's doing to an audience, even addressing his patients when they're under anesthetics and acting as if they reply. He tends to get very cranky when he hasn't had his morning coffee; if he goes too long without it, he may start threatening his patients with purposely-induced comas or even death while he treats them.
He first appeared in The Jacksepticeye Power Hour #2. He later reappeared in Amateur Surgeon: Christmas Edition and a third time in Bio Inc. Redemption #4. In the latter, we see that because he has allied himself with Jack, he can become susceptible to the mental influence of Antisepticeye, who despises him for helping their creator.
As he performs surgery to save Jack's life, he begins feeling the effects of Jack's pain and becomes increasingly anxious and disoriented, desperately pleading with the viewers: "We need to save him, we need to save him -- I need your help! Save him! Save Jackseptic..." A moment later, he mentions "ANTI-depressants", stuttering and glitching. The effects quickly worsen, to the point where Schneeplestein's voice and mannerisms start blending with Anti's, but when Jack flatlines, Schneeplestein cries out for him: "Jack! Jack, no! My friend! NO!!"
Directly after this quote, Anti takes over the screen, and says that Schneeplestein may have thought he could save Jack, but he was too weak to do so. It is unknown if Schneep has since recovered from Anti's attack.