Albus Dumbledore : Severus... please...Severus Snape : Avada Kedavra!
Read more Professor Albus Dumbledore QuotesFrom: Harry Potter and the Half-Blood Prince (2009)
Ron Weasley : You heard Snape say he's made an Unbreakable Vow?Harry Potter : Yes. What does it mean?Ron Weasley : Well, you can't break an Unbreakable Vow!Harry Potter : I worked that much out for myself, funny enough.
Lavender Brown : Ah! See? He senses my presence.Lavender Brown : Don't worry, Won-Won! I'm here. I'm here.Ron Weasley : Her... my... nee. Hermione...Albus Dumbledore : Oh, to be young and to feel love's keen sting.
Severus Snape : Has it ever crossed your brilliant mind that I don't want to do this anymore?Albus Dumbledore : Whether it has or it hasn't is irrelevant; you gave me your word.