It's nice and sweet that you want to run your girlfriend's character along side you, but honestly, unless you are soloing, you are denying other people a spot in the EQ by doing so. Also, since most EQs are about reaching the goal as quickly as possible to try to fit in 3 or 4 runs, even on SH, having a non-active player just running around reduces the chances of that happening. The only EQs that this may be okay-ish in are ones that are just "kill enemies for 20 minutes" like the guerrillas ones.
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