Filchikens!

Lindsey shook her head and started laughing. The girls looked at her, all with a confused expression on their faces. 'So, it's an invisibility potion, huh?' she sniggered.

She felt a strain on the sofa beside her and hugged him as the others cried 'Dennis!'
'I gotcha back!' Dennis laughed.

The girls all grabbed a pillow and randomly threw them at the place where they heard Dennis' voice. All of them missed and a voice was heard from behind Kate and Leyla. 'That was for the dungbomb!' Kate brabbed randomly and felt her arm close arounf something. She grinned evilly and pulled. Dennis fell onto Leyla who grabbed him. Soon enough all five of them had him and were marching with him to the boy's dorm. They opened the door to the fourth year boys dorm and the boys looked up.

'What've you got there?' Nick asked, raising an eyebrow.
'You'll see... Hopefully!' Nat laughed.
'Where's the bathroom?' Holly asked. Lindsey, who had her hand over Dennis' mouth as she heard Dennis try to scream.
'Over there, why?' Tom asked.
'You'll see...' Lindsey grinned. They marched in and chucked him in the shower.
'Just in case you didn't take our advice last time!' Leyla laughed. Lindsey turned on the shower and sprayed him until he was visible again. They could see him scowling.

'Damn it.' he frowned.