Malware/Virus hiding in folders it makes for itself with random names

I have some sort of what I assume is malware taking up ~30GB of space on my hard drive. Every time I locate the folder it's in, which is visible, the folder disappears and comes up under a new name. First it was under 'DigitalLocker' and then it was under 'Globalization'. I figure there's no point in trying to just delete it because it will just hide itself and show up again somewhere else.

This is my dad's computer and I had assumed at first that the 30GB file was just the Google Drive he'd downloaded syncing loads of stuff onto the computer. That made sense until the file renamed itself. It's like it's trying to hide from me. What can I do to get rid of it? My dad doesn't want to try deleting the file in case it's 'important data' (nothing important on this computer actually but... eh... whatever makes him happy)

Update: Okay we tried deleting the file. Didn't work. Sent file to recycle bin and then cleared recycle bin but the 30GB is still being used by SOMETHING.

Welcome to the forum, Dragon Girl !

Please use the Farbar Recovery Scan Tool.
Download: Farbar Recovery Scan Tool Download
Select the version that applies to your system.
Save it to your Desktop.
Double-click the downloaded file to run it.

When the tool opens, click Yes to the disclaimer.
Press the Scan button.

When done, the tool makes a log, FRST.txt, in the same directory from which the tool is run (Desktop).

Please provide the FRST.txt in your reply.

The first time the tool is run, it also creates another log: Addition.txt
Also post the Addition.txt in your reply.