I think pink blood is either for yuri and hyo subunit, aespa subunit or nct subunit. If it's for aespa subunit it'd be a great idea to introduce new members debuting them as a subunit this summer while aespa is preparing the album and then the new subunit will join aespa for the album comeback.
Probably pink blood will end up being something we didn't expect at all and not related to aespa