Sirius Black:
Sirius doesn't really jerk off, he prefers to wait until you come home because his craving for you just intensifies, so by the time you come home, you're gonna be in bed for the whole evening.
Remus Lupin:
Remus believes that jerking off when your are not there is a bit rude. He's a bit old fashioned. However, he does find himself getting hard when your do random things, always tries to ignore it, but it never works out.
Severus Snape:
Sev jerks off sometimes, mainly when you aren't at home for long periods of time. He just misses the touch of your skin on him.
Lucius Malfoy:
If he does, you never catch him. He just summons you to his office when he gets hard thinking about you.
Draco Malfoy:
Plenty of times during the week. He just can't stop thinking about you, and sometimes it leads to naughtier thoughts. When you are on your period, he jerks off a lot, especially when you are asleep and cuddle into his torso, or wiggle your bum against his dick, making him immediately hard.
Bill Weasley:
He finds himself doing it in the shower a lot, especially if your two had a great night, but didn't have time in the morning.
Fred Weasley:
He does jerk off, a lot. A lot of naught thoughts run through his mind when he is bored, and it usually leads to some hand action.
George Weasley:
George does jerk off, but not frequently. He prefers to have sex with you than jerk off.
Neville Longbottom:
Nev seems to be innocent, but his mind is something else. When he sleeps, his mind drifts off to something dirty, he often wakes up hard and you asleep. He would then jerk off whilst you slept.