Well, he could be worse.
Panel 1: A hallway in Sigma’s apartment building. Rho, walking carelessly, waves with a smile and says “Oh! Hi, Sigma!”. Sigma is walking in the opposite direction (towards Rho) with his cane, and raises his eyebrows at the sound of Rho’s voice in front of him.
Panel 2: A close-up of Sigma’s head. He raises one eyebrow with a suspicious expression and says “Hey…”
Panel 3: Same close-up, but now Sigma is visibly annoyed. He says “Were you just leaving my apartment?”
Panel 4: A close-up of Rho, who raises both hands up to the level of his shoulders and shrugs. He says “Oh, don’t worry! I saw that no one was home so I left—”
Panel 5: Rho says “I’m not gonna walk into people’s homes when they’re not around, that’s creepy”. Sigma angrily replies “You shouldn’t do that in general”