We'll dance inside the song
Seven years passed far faster than Severus would have preferred.
Whilst the Sanare Nervos potion had been largely successful for the majority of the trial patients, including Remus, the man did still suffer some pain in his right hand. Master Robyn was not at all happy with this. He hypothesised that Remus' lycanthropy had an effect on the potion's efficacy - that his werewolfism caused the potion to metabolise too quickly inside the body. Master Robyn was still attempting to tweak the formula to make a universal version of the Sanare Nervos.
Unsurprisingly, Severus passed his Potions apprenticeship and was now Britain's youngest Potions Master and the youngest Potions Professor ever employed at Hogwarts School for Witchcraft and Wizardry. The potion that granted Severus his mastery? An improvement on the wolfsbane potion that allowed the werewolf to use it on the nights of the full moon, and not a full week preceding it. However, the potion that made Severus internationally famous was his creation of a male fertility potion that allowed wizards to carry a child full-term. The pureblood factions were ecstatic. The potion meant that the number of wizarding children would increase - something that had plagued them for generations - and Severus had received many monetary contributions to create a potion to help support female wixen pregnancies as well.
Known to only a select few, one of the trial patients was Remus John Lupin, who successfully carried a child full-term and gave 'birth' via wixen caesarian on the 23rd August 1981 to a healthy son. Known to even fewer was the child's name - Andras Marvolo Snape.
After rediscovering one another in a ward in St Mungo's, Severus proposed to the werewolf after a few weeks and they swiftly bonded a month later with Bellatrix, Rodolphus, Rabastan, Lucius, Narcissa, and Regulus as witnesses. Remus invited no-one from his side of the but he found he didn't mind so much. He hadn't forgiven his former-friends and they never even made any attempt to apologise or reconcile. Remus couldn't say he missed them overly much.
Whilst Severus and Remus were largely happy and content, they had faced their share of trials and tribulations, from minor disagreements and misunderstandings to serious emotional upheaval. Regardless, they always reconciled any disagreements (after a period of silence and reflection) and always comforted one another, and provided quiet support during a crisis. Severus was the constant lover whilst Remus was recovering in St Mungo's - visiting daily to provide companionship and devotion - and Remus steadfastly held onto Severus as he sobbed into Remus' shoulder upon learning of the 'death' of the Dark Lord - Severus' pseudo-father.
As Severus, exhausted after a grueling day at Hogwarts, entered the cottage that the small family shared, he smiled softly at the scene that greeted him. Andras raced to greet him at the door, waving a sheet of parchment with brightly-coloured shapes and proudly wearing paint splotches on his round cheeks. Severus swiftly scooped the young boy onto his hip and stepped further into the room to kiss Remus soundly on the lips.
Andras made noises of disgust but happily snuggled Severus' shoulder. "He's tired," Severus commented fondly, whilst pressing a light kiss to his son's head.
"He stayed awake to see you," Remus answered softly, noticing the child's eyes beginning to droop. Severus began to apologise for his late hours but Remus waved his concerns aside. "We're happy, Sev," he whispered, "I know you're needed at Hogwarts during the day but you're always here for us in the evening. We can't complain."
Severus carefully placed his son, who had swiftly fallen asleep, onto the sofa and then pulled Remus into his arms. Staring into his husband's eyes with endless devotion, Severus whispered "I love you," before capturing his lips with his own.
Severus began crooning sweet-nothings into Remus' ear but after a few moments, Remus danced away from his husband, cast a monitoring charm on their sleeping son, and eagerly pulled Severus into their bedroom.
What makes the one to shake you down
Each touch belongs to each new sound
Say now you want to shake me too
Move down to me, slip into you