'Getting groped is just part of a normal night out'
Sexual assaults in nightclubs, bars and pubs are now so common, police say people don't bother reporting them.
Lottie is 18 and tells Newsbeat she regularly gets assaulted and says it's now "just part of the night".
"I've had my boobs grabbed, my bum grabbed, I've had people put their hands up my skirt and down my top."
Now a new campaign to get people to come forward and report sexual assaults has started in Bristol.
Avon and Somerset Police is the latest force to try and do something about it.
"Our message is clear - it is not acceptable and there will be consequences for anyone who behaves like this in our licensed premises," it warns.
Police Scotland, West Yorkshire Police and the Metropolitan Police have run similar campaigns.
Lottie's older sister Anna, 20, says she often has to deal with groping in clubs.
"I've had one guy come up to me in a totally inappropriate situation and grab my boobs, and then he was just holding them.
"I was just shocked and didn't know how to react.
"His friend laughed and said 'he's just drunk, never mind him'."
Lottie and Anna say they sometimes wear shorts underneath their skirts on nights out to prevent assaults from happening.
"Unfortunately you've got to be prepared and that's the way it is," Anna tells Newsbeat.
"I feel a bit like prey - there are a lot of predators around who will just grab you," Lottie adds.
A Buzzfeed News investigation found more than twenty sex attacks at pubs, bars and clubs in England and Wales were reported to police each week last year.
The figures, which were provided by police, show the vast majority of victims were female.
Campaigners warn that number is probably much higher as many assaults don't ever get reported.
"I've never thought to report it because it happens to me every time I go out.
"It's just what happens," Lottie says.
After hearing about Lottie and Anna's experiences, Chief Inspector Marie Wright from Avon and Somerset Police set up a campaign to try and get more women - and men - to speak up.
"It's sexual assault and no-one has the right to touch somebody in this way without their consent and it needs to stop," she tells Newsbeat.
"If you're assaulted you should tell someone.
"It may be that you don't want to tell the police, so tell the bar staff, or the people on the door or someone in the nightclub who works there."
She says getting venues involved is key to their campaign.
Pub landlord Angelo was forced to take action after he found out two women had been sexually assaulted on the dance floor at his pub - but didn't tell anyone.
The pub's bar staff and DJs were trained in how to spot inappropriate behaviour on the dance floor, how to help victims and handle perpetrators.
"It's a tough one, especially if people don't come forward and make a complaint to us.
"In general they don't - so it is our responsibility to watch and make sure that if anybody looks uncomfortable, you can go up and say 'is everything ok?' and go from there."
Just over a hundred pubs and clubs have signed up to the Good Night Out training scheme across the UK.
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