BUR #20969 has been approved by @evazion.
rename ein_(phantom) -> ein_(phantom_of_inferno)
rename zwei -> zwei_(phantom_of_inferno)
deprecate zwei
There are two characters from an obscure Nitroplus VN Phantom of Inferno called Ein and Zwei. Given that both were named after German numerical, and that these two currently have a rather ambiguous tagging (Ein is tagged as "ein_(phantom)" in spite of the series's full name, while Zwei is tagged simply as "zwei" with no qualifier whatsoever), I think these tags should be renamed accordingly.