Fenris found it odd that both the twins were referred to as 'Hawke', even by their own family. Fenris had assumed at first it was some strange Ferelden custom the group had adopted regarding twins but that two proved to be false when he questioned a pair of Ferelden born twins in Darktown when having to meet with the abomination (Anders if you must).
Fenris played along for a while, finding it strange however more simplified it may seem. Fenris himself having a twin, and being refereed to as the same name, and actually liking it as the Hawke twins seemed to. However this may have just been his own bitter feelings over situations of him being mistaken for other slaves back in Tevinter despite having white hair and lyrium markings which generally weren't found on most average slaves.
Fenris' problem with referring to the Hawke twins as each just Hawke began to occur however when his heart began to favour the both of them. He would think of Garret's beard brushing against him in lazy early mornings, then immediately imagine Marian's hands running through his hair in the evening after a long hard battle. Fenris feared the risks a relationship entirely, let alone the risk of loving both the Hawke twins.
Another issue that did not help to resolve his feelings was he had never seen Marian and Garret together. It was so easy just to imagine the two being the same person, both having a similar wit and views of the world, and the constant mannerisms of the group that they too seemed to see them as one. This dilemma of his wouldn't be easy to solve, so he went to his next best strategy, bitter ignorance.
This seemed to rise the group of misfits he reluctantly called friends, and Anders. Varric and Isabela seemed to chatter words about the two of them behind his back on missions that made his ears burn, or were they turning red over the exquisite glance he just had of Marian's chest when she stretched after battling a group of coterie thugs? Well Anders and Merrill were far more blunt with their disapproval of his actions towards the Hawke twins. "Were you always this bitter or did you have to train?" "You should be nicer to Hawke, she's a lovely lady."
At the heat of the predicament he, at the worst moment, found himself awaking next to Marian and having his first thought being "This is not Garrett's beard scratching against me." As he tried to quietly leave Marian awoke herself and started throwing accusations at herself of being a bad lover, and Fenris feeling a coward to his own emotions spun half lied tale of Danarius and memories of the past being ripped from his very hands. True his memories did come to him and leave at his climax, but the sweet taste of Marian on his lips had eased him some, otherwise he would have left instantly after. Marian however didn't seem to pick up on that and for the next month both of the Hawke twins glanced at him, each seemingly wounded in their gaze and under all their bravoed wit.
The next time Fenris had spoke to Marian without introduction was when he had the striking realisation she may have conceived. "Marian," he called to her when the two were alone running errands. "Are you with child?" Marian stopped abruptly. Stiffly she turned to Fenris with a look of pure horror. "Maker no Fenris!" That was the end of all excess conversation between the two for another month.
When the mother Hawke had passed, mutilated and murdered by a sadistic blood mage stuck trying to recreate his memories he visited the house. Only Marian sat and like a fool he told her he did not know what to say when prompted by her. The act earned him his first truly enraged response from the mage who hissed for him to leave.
Now he found himself in another favourable, unfavourable situation. Saved from a trap by Garrett and finally free from Danarius only to be trapped under within his own carnal desires. Garrett leaning down close to his ear had whispered in his low tone and Fenris was gone, only to be replaced with a primal desire which lead the two to Hawke's home and his bed. No, wait a minute. This was Marian's bed! Fenris had now returned to the world of reality and pushed Garret from him.
"I will not do this here! Not on your sisters bed! I have too much respect for her!" Fenris protested, earning the confused gaze of Garrett Hawke.
"Fenris love, my sister is dead. This is my bed." His heart dropped. Marian had passed? Was she murdered? Killed by templars or a demon? Oh how could this have happened to her.
"Marian..." He murmured, followed with curses in every language he knew as Garrett leaned away from the elf who now clutched his eyes crying.
"...Yes." Garrett responded. Fenris now whipped his now reddening eyes in anger at the mage.
"That was a foul joke Garrett! How could you have not told me she was dead!" Lyrium flaring as blue as the sky Garrett now stood up from the bed, his face showing a look of complete confusion.
"I told you my sister was dead ages ago, you've commented more than once on it. Tell me Fenris did you hit your head in the battle earlier?"
"I never knew she died. I would not be here if she died."
"Come now Fenris you never even met the woman."
"Never met the woman. Garrett I loved Marian as I loved you!"
All was silent. A mouse within the room ran across the floor. The candle crackled. Garrett began to laugh like a madman.
"Oh Fenris, my dear Fenris how I love you." Garrett walked over to Fenris, clasped his face between his slim hands and kissed his tears away. "Could you have not known for the 7 years we have been together could you have been so blind." Fenris pulled away and began opened his mouth to protest.
"Shh Fenris, still the ache in your heart and I will show you how Marian is alive and well." With a smile on his face he removed the top half of his armour, followed by his shirt before the silently stunned Fenris. There before him, upon Garrett's own chest, lay a pair of bound breasts.
"Should I shave my beard," Garrett called amused. "You would see that I am in fact Marian."
"I-I don't understand."
Sitting down next to him Garrett grasped Fenris' hands. "Fenris listen to me. I was- am, both Garrett and Marian. I'm what's called genderfluid. A man at times and a woman the next."
"I-I still don't-"
"Think Fenris. Marian and Garrett were never in the same place at once, everyone referred to them by their last names, including you."
"But I-I-I thought you were a set of twins!" This had made Garrett laughed again, tears forming in his eyes while Fenris himself began to turn red.
"You're hilarious my love." Garrett spoke before being crushed to the smaller elf's chest.
"No," Fenris spoke, his voice barely a whisper in complete joy. "You are just easily amused." Fenris smiled at him before drawing Garrett into a kiss to continue where they left off.
"So to clarify, of male feelings you bind your chest, use magic to grow a beard, deepen your voice and bind your breasts while going by Garrett, but female feelings you shave your beard and address yourself by your birth name?" Fenris asked the next morning as he lay in their bed, watching Marian shave her beard off.
"Mhm." She responded, then cursed as she nicked her chin with the blade. Fenris laughed, arising from the bed in all his glory to move over to his equally naked partner and kiss the injury.
"Good, I wouldn't have you any other way."