I just found out that they really do Kara/William's romance. In the same time, I shouldn't be too surprised but well, I hoped that producers and writers wouldn't follow the same path as Kara/Mon-El (they begin as antagonists then suddenly, they fall in love). How stupid I was to think that people in charge of the series would be more imaginative to propose us a romance which won't turn to a fiasco like Kara/James - Kara/Mon-El and Lena/James.
-> have they really learned nothing from their previous attempts to associate Kara or Lena with partners far from being up to par. Some of you will answer to wait and see how Kara/William turns before judging but hey, it is CW and as for 5 series of Star Trek, writers don't know how to write a romance which truly
arouses our interest, works over time and with a happy ending in the finale. Result: given the more or less negative reception from viewers and here, I already see the backlash, they will be forced to find an acceptable solution to explain the breakup .For Kara/James, it was a change of heart from Kara's part, for Kara/Mon-El, it was an emergency departure for Mon-El to not to be affected by a deadly virus (I never undestood why they had brought back a Mon-El, coming from the future and married but well...) and for Lena/James, it was further to emotional blackmail after he practically asked to his brillant and independant girlfriend to choose between him and her work. So, I guess that it will the same for Kara/William but the questions are how long will it last before the offical end of their relationship (usually it is about one season except for Kara/James where it has lasted something like 2 or 3 episodes, if I remember well) and how it will end? It seems that some people already think that William could end up being killed by Lex, after going too far in his investigations or in trying to thwart his plans...such a scenario would be a first but according to the clear open threat given by Lex in the gymnasium, it could be a possibility, don't you think? And a completly realistic one as seeing as 1) everyday, journalists/reporters die tragically as part of their profession and 2) no matter it is Lex or Lex 2.0, neither of the two is a man getting some scruples so if something or someone aggressively interferes in his plans, he will dismiss it/him-her with the back of his hand, using by the way violence (whether physical or mental / psychological)
About the idea of giving to Kara a male love interest, I can understand that with Alex being a lesbian who is living (boring, sorry I couldn't help it but after almost 1 season, I really can't get involved in their SL) a romance with Kelly Olsen and Nia playing a trans superhero, the producers think that LBGT's fandom is already well served, that SuperCorp is not necessary though still the most popular fandom of Supergirl since S2 when Lena entered the stage (even Alex with whoever girlfriend she had/has never managed to be as popular as SuperCorp!). Without forgetting that since the beginning there was no indication of any lesbian tendency on both sides : Kara told clearly to Winn in S01xE02 that she wasn't a lesbian and Lena, of the little we know of her past love life, seems to have dated only men BUT why absolutely want to associate in a romantic way, these 2 powerful/brillant and independant women with men who clearly don't measure up with them, tending to treat their girlfriends rather badly (in underestimating/behaving like jerk: Mon-El has done it with Kara and later, James did it with Lena so, I don't see why it wouldn't happen with William with Kara, the latter trying to gain control over her at one point or another of their relationship, especially if he pursues his "vendetta" against the Luthors and they have an expected disagrement about how to treat Lena: William will see her as a Lex sister and a Luthor so, a great potential danger while Kara will continue to defend her though both are cold (to each other).
Paradoxically, I started to compare Kara / William with Kara / Mon-El but according to what we already saw and will see in the next episode, I could have compared this romance to Lena/James too:
a lovestory come out of the blue (William was in what, 3 to 4 episodes since the beginning and relatively spaced from each other to the point that I had practically forgotten his character and I'm pretty sure to not be alone!) and suddenly she decides that William is not that bad and could make an acceptable boyfriend?!

After to have apparently lost her friendship with Lena then lived the tragic events in Crisis, I would have expected something else than seeing Kara suddenly careing about her love life! Being a single hero is not a shameful thing!
And to end, what about her and Lena? Producers introduced this season in telling that Kara/Lena's relationship would be the central point of this 5th season and it was the case until Crisis, but with Kara/William's romance, I guess that her relationship with Lena will pass into the background (in the same time, Lena has her own storyline and is quite busy to work with Lex) but I note that when she still dated James, writers have chosen to distance her from Kara when they were still good friends, James suddenly becoming her pillar (he proudly said that he knew her by heart, better than anyone, including Kara with whom she spent an infinite time but well -> if he knew her so well, he would have never ask her to choose between him and her career, by the way!) at the expense of Kara and it seems that they want to repeat this pattern with at Lena's place and William at J's place ... until Lena comes back in the game in getting closer to Kara again after I don't know what events and from there, William will return in anonymity as if writers didn't know how to translate that people can equally lead a deep relation with a friend (well ok, on this point, we will have to wait a little longer before seeing Kara and Lena close again) and a love life, without one needing to take precedence over the other!
-> I wonder how writers live their lives: I mean, don't they know why and how people fall in love; how they live their romance romance and how/why it ends? Insread, they choose the drama and backlash!
