If Christ Jesus is the `first` then there must be others to follow. We are to be Sons Of God - not sinners saved by Grace.
We can only manifest as Sons Of God when we are Spirit Filled with transformed minds.
Christ died: → to keep us from having to go to Hell → to enable us to be Born Again as New Spirit beings → to baptize us with His Holy Spirit → to enable us to partner with Him in the Kingdom work → to enable us to manifest the character and power of His Holy Spirit → to empower us to rule and reign in the Earth → to keep us in eternal intimate personal relationship with Him
Until then our perfect spirit selves are held back by the corruption in our body and soul.
Note that we are born of the Word and the Holy Spirit. → the Word is what Jesus said and who He is → the Holy Spirit is the inspiration and essence of Jesus. → we are begotten of the Holy Spirit as New Spirit beings on the authority of what Jesus has accomplished for us.
So, the concept of virginity with respect to the 144000 must relate to their total commitment to Christ Jesus. They are not torn between the carnal and the spiritual.