Default Can Xposed framework Brick my phone

Ihave a phone called my saga c3 it is a rooted mtk6572 no custom roms or recovery and I dont want any custom roms. If I download xposed will it edit my framework files and then messing them up and the device will be bootlooped . I heard that it doesnt edit them but in memory, so anyways tell me how does this app work to modify how your device look and is it safe?

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