First of all many people think that Eren and Mikasa are adopted siblings due to the fact of living together.So I will say Mikasas' feelings First and then Eren with extreme detail okay .So let's begin:

1)First of all most people believe that Mikasa and Eren are adopted siblings but it turns out they are not because Mikasa was taken in (not adopted )by the Jeager family at the age of nine.Despite living together for one year or less this isn't enough time to consider Carla and Grisha as her 'new father and mother 'and especiallyto think her saviour Eren as a brother but it only contributed in making her to love Eren more during the time they lived together.But people say that Mikasa sees him as family as she stated many times in the anime/manga but other characters don't see them as siblings such as Levi who says that he is her "precious friend"or "childhood friend".



However family it is considered by many people that it consists of relatives but they are wrong by a large degree as family is also considered a husband , your bestests friends etc.Especially a person who saved you ,take you in his family,is your bestest friend and love him.Last but not least Hajime Isayama stated in one of his interviews himself that Eren and Mikasa are not siblings in any possible way.

2)she blushes when Eren is said to be her boyfriend as it was shown by Ian when he said that:



She only says that he is her family not brother or anything else.Family for her is consisted of people she deeply cares about.

3)Eren is the most important person on Earth for Mikasa. That's undeniable. Since the day he saved her, she always cared about him, protecting him that people think that it has become an obsession for her but no its not, because if he died instead of seeing a collective and calm Mikasa we will see a suicidal ,cold hearted and depressed Mikasa which we don't want to see .Just see it like this Eren is a chair and Mikasa is the person who is sitting on it .If the chair(Eren) falls or breaks(dies) then the person who is sitting on it (Mikasa)will fall as well (becomes cold , depressed, suicidal.),as long as the chair (Eren ) keeps standing up (being alive )then the person who is sitting on it (Mikasa )will keep being the same (collective ,calm,protective etc.)We could say that she is just grateful for saving her, years ago. That's true, indeed, but there's something more. Mikasa said that as long as Eren is here, she has someplace she can return to.We could say that Mikasa feels Eren as her home which means that she finds him as a person who comforts her ,gives her warmth ,being at her side when it is needed and many other things.Mikasa revealed in chapter 45 or pisode 33 that the only thing she wants is to be by his side:





4)She was jealous when she thought that Eren might have special feelings for Annie (which is not true)in episode 24 or when Eren was talking to Krista( chapter 70):



(episode 24)



(chapter 79)

5)Ah shit I forgot about this .When Mikasa learned that Eren was dead from Armin in episode 7 she pretended that she was calm but that didn't fooled Armin as he saw her face and had an expression that said 'what the fuck why  is she not crying'but then he released that she was in so much mental pain that it lead her to commit suicide but was later saved by Eren.Also she didn't blame Armin because she blamed herself for Erens' death because she left his side.And when Eren was found alive she hugged his body so tight and cried until she had no more tears while blushing:





(😭😭this one of my most heartbreaking moments that I have ever seen.)She cries tears of relief and happiness after she realize that everything she sawbw8th her own eyes was real.

6) Armin supports her love for Eren:



You see here Armin knows Mikasa feelings about Eren and supports it as he waved good bye to mikasa smirking making a face showing that he knows the reason why  mikasa is staying , making Mikasa blush as she thought what was armin thinking about.

7)After chapter 36 she started giving eren personal space which is very significant for their relationship as they become more closer.

8)the most important for all Eremika shippers is chapter 50 /episode 37.When Eren didn't succeed to save Hannes, he cried and said he was useless. Then Mikasa told him "that's not true". This is pretty important: it means that she doesn't think he is useless, and she made him remember what he did for her : she thanked him for being at her side, for teaching her how to live her life, and, the most important, for wrapping his scarf around her.







This scene right here shows that mikasa was going to kiss Eren but it didn't happen because of the titans if there wasn't any titans the kiss would have happened.The scarf in the anime is red which indicates the red string of fate (Google it if you want information)but in the manga this does not exist instead of red her scarf is black.Also  isn't it a little suspicious why hajime isayama wanted this Eremika moment perfect designed by a person who design Eremika moments or the designer himself.

9)Also in anime at episode 25 this scene indicates her love for him:



Here mikasa is shocked by what it is hearing from her crush Eren as she cupped his arms saying that she is relieved.Also haven't you noticed that in every important Eremika scene there are always those godamn purple flowers in each scene for example in episode 25/chapter 36 by the window there is a vase of purple flowers and in episode 37/chapter 50 there again purple flowers first I thought it was a coincidence but twice something is wrong there might be Sth that these type of purple flowers symbolise .After searching the meaning of these flowers this is what I found:
Flowers with purple colours means that two people will grow closer to each, like trust each other many other things but it also means maturity which logical because after every scene where erens personality changed these types of flowers show suddenly up.

10)she doesn't have any interest in other men as it was shown when mikasa turned Jean down coldly without even thinking about if he broke his heart or not or even his feelings. 

11)Also in chapter 101 she says that same words that wren said to her when he saved her from the kidnappers and is it me or she looks like she going to cry if eren refuse to go home.

I THINK THIS IS MORE THAN ENOUGH EVIDENCE FOR EREMIKA COMMENT DOWN BELOW PLEASE AND SAY YOUR OPINION!!!!!!!!