Pantalone pining for fragile!Reader...he knows he shouldn't, but he's seen how happy they are with Dottore (and ...heard more than he probably should have; the walls of the Doctor’s lab are thinner than you'd think), how happy he would be with them instead. They are beautiful and intelligent and kindhearted, and he yearns for them not just emotionally but also... physically. So the next time he runs into Reader, all those salacious thoughts come to a head, and he can't help himself...when Reader looks at how nervous and awkward he is and realizes he's hard 🙈
Pantalone was conscious of his greed. Very much so, in fact. When he saw something he wanted, he simply obtained it, and it was usually not too big of a hassle, considering his current status and wealth. And on occasions when it proved to be a bit more work than usual, just a bit of effort and planning, maybe even scheming was more than enough to bring things into his favor. It had been his tune for so after becoming a Harbinger, that wanting something that he couldn't get was almost like a cruel smack in the face that reminded him of his younger days. Specifically, the target of his longing being none other than you.
He had never intended on developing... feelings. Pantalone was an expert in being charming, even borderline flirting toward others, but they were always empty. They held no truth, no substance, just greed for his own ambitions. He was almost like that toward you in the beginning, but not quite due to the circumstance of you literally being The Doctor's partner. But then he realized why Dottore seemed to become a different man in your presence. Being around you felt like acceptance. It felt like understanding. It felt like an embrace that would never leave, always lingering no matter what. And perhaps that was something both of the Harbingers needed... but obviously, only granted to one. Deep down, Regrator felt envy somewhere. On the surface level, Pantalone knew he should be grateful that you wanted to spend so much time with him, but it wasn't enough. No, he didn't think it could ever be enough. He too, wanted to shower you with everything he could give, just like Dottore did.
And as Pantalone had come to realize, Dottore was no stranger to showing you exactly how much he cherished you. Sure, spying on other people's private matters was kind of Pantalone's job sometimes, but not like... this.
"H-Hah... Zandik, i-it's so much..." You certainly weren't trying to hold back your noises, most likely due to Dottore's demand. From where Pantalone stood, that was the most he'd get. He could at least tell you were nude, from the clothes strewn around Dottore's desk, but the scholar's body was large and protectively covering yours, so all of your more private areas were concealed save for your legs and arms wrapped around Dottore, and your face buried into his neck. Pantalone thinks himself a man with his guard constantly up, but he nearly forgets the precarious position he's in, when he thinks about how easily he could hoist you onto his own desk and have his own way with you.