, a secondary aspect of karkat's hemokinesis is blood-linked empathy via proximity
to break it down, karkat can sense the emotions of any being with blood through
their blood by being near them. his range extends fifty feet, though it fades out gradually the further away you go. his power is much, much weaker at fifty feet than it would be if you were, say, physically touching him. this power also extends to static blood -- that is, blood outside someone's body, or the blood of a dead person. this blood will carry the last emotion a person felt before they lost that blood or they died. another subset of this power is mild emotion manipulation through blood
which boils down to karkat can soothe more negative/volatile emotions, and bring a character back to a more "base" or peaceful emotional state. this influence vanishes once physical contact is broken.
now, as for the second one, i will never, under any circumstances use it in a thread without seeking your ooc permission first. for the first one, karkat generally avoids talking about it, anyway, but i'd still appreciate if you filled this out for me.