So I rolled with it.
Stranger: hi my name is voldemort
You: do you ever worry you might be too good looking to get a boyfriend?
Stranger: well, i am a boy, i am voldemort
You: voldemort, you probably don't have this problem
You: but i know a lot of other gay men think they might be too good looking to get a boyfriend
Stranger: you are gay?
You: but i imagine it's the converse for you, right?
You: too ugly is it?
You: seen as though you're kind of crossed with a snake
You: got those weird nostrils going on
You: i mean.. y'know... maybe some people are turned on by it
Stranger: well i dont care about girls i just want to kill harry potter
You: but i suppose you must go on some pretty ffreaky dating sites for the kind of guys that are into that
You: ah, is he your crush?
You: i wouldn't have thought he's your type
You: doesn't have any piercings or tattoos or anything
Stranger: i dont care about relationships because i am voldemort
Stranger: i am supreme
You: i can tell it's beating you up insdie
You: secretly you just want harry to pop up and give you a big ol' hug
Stranger: no... i dont
You: come now voldey
You: is it ok if i call you voldey?
Stranger: i guess
You: ok good
You: listen voldey
You: you just need to chill out
You: i understand if you're not really really good looking and handsome like harry potter or hermione or luna or ron you might find it harder to get a long term partner
You: but just relax
You: going around killing people isn't going to make it happen any faster
You: you just need to chill out and be paitient
You: and when it happens it won't even matter that it's taken you...what? 19 years?
You: to find someone who cares for you as much as you care for them
You: don't worry
You: we're all on the same boat in life
You: right enough you have slits for nostrils
Stranger: i like my face...
You: but you'll find a man who will see through that love just love you for who you really are
You: well there you see
You: you look really nice
You: and you have so many extraordinary wizarding powers
You: you must be pretty good at having sex
Stranger: im not gay...
Your conversational partner has disconnected.