Bloom and Sky are a close romantic couple but they have many ups and downs. This is the only couple where the girl has a known ex-boyfriend (Andy) and the boy has a known ex-girlfriend and fiancee (Diaspro) as it is unknown if the other couples have dated before or if their ex's will ever make an appearance. Sky asked Bloom if she would be his princess at the end of The Secret of the Lost Kingdom and asked her if she would marry him in Magical Adventure, both of which she accepted.
In Season 1, they meet for the first time and are quite close and they are both happy with each other, forming a strong and close friendship.
Their relationship was a little shakey after Bloom found out that Sky and Brandon switched identies, but they were able to work past this and become close friends again.
At the beginning of Season 2, Bloom and Sky have become closer but after hearing a rumor about Sky and Diaspro being together, Bloom is wary of her relationship with him. Sky assures her that nothing is happening between him and Diaspro. When Sky called her to meet up with him and have a serious talk, when in reality he was planning on asking her to be his girlfriend. Bloom agrees to meet him at Red Fountain but later starts thinking that he is going to break up with her. When the Trix attacked Red Fountain to obtain a part of the codex, Sky was hit with one of Icy's attacks. This put him in a suspended state where it seen like he died. Bloom is heartbroken and tries to revive him. She is successful and immediately afterwards Sky asks her to be his girlfriend to which she agrees. In Season 2, Bloom and Sky take part in a mission to rescue the Pixies. On the mission, the new girl, Aisha, impressed Sky with her survival skills and vice-versa. Though this was out of respect on both sides, it created tension between Bloom and Sky as Bloom got jealous.Bloom developed a crush on the new Alfea teacher Professor Avalon (who was actually fake Avalon at the time). Sky took notice that Bloom spent most of her time with Avalon as he was helping her understand her past. During the unveiling of the new Red Fountain, Bloom left Sky and the Winx for Professor Avalon. Sky became jealous that Avalon was recieving so much attention from her and was becoming all that she would talk about when they were together.
Towards the end of the season, when Bloom was captured by Darkar, Sky took part of, if not led, the Rescue Mission to save her. In the Realix realm where the Winx and Specialists were paralyzed by Darkar's Magic, Sky was able to overcome his paralasis and make his way toward Dark Bloom. He was able to turn Bloom back to normal by telling her that deeply he loved her.
Sometime after Darkar's defeat, it was stated that Bloom and Sky had a fight, but she wanted to make up with him. The extent and matter of the subject is unknown. After making up, Sky was going to announce to the whole world that he loved Bloom in his party on Eraklyon. Unfortunately, Diaspro, wanting revenge on Bloom, gives Sky a drink containing a spell of Valtor. The drink causes Sky to be under her control where he states to everyone he loves Diaspro instead of Bloom. Devastated, Bloom tries to talk to him, but Diaspro says the Winx are witches causing a battle between the Winx and guards. With the Winx now considered enemies of Eraklyon, Bloom is forced to leave Sky for the time being.
Bloom returned to Eraklyon to figure out what happened and finds that Sky was branded with Valtor's mark. Stella stepped in and used her fairy dust to free Sky after Bloom realized she didn't have the power to free him. The two later reconcile with each other.Magic Dimension when Sky came there to comfort her. Bloom and Sky were later seen dancing in the fields of Alfea. Sky was telling Bloom something but he was disturbed by a ship from Eraklyon.
Later on, after Bloom dreamnt about Daphne telling her about amission to Domino, she later wakes up and goes into the living room and saw the Winx and the Specialists (minus Sky). At the end of the movie when they have saved Domino Bloom has a princess ball, she dances with Sky. While dancing they pass by Stella and Brandon, Brandon passes a box to Sky which contains a ring. Sky whispers into Bloom's ear saying "will you be my princess?". Bloom says yes in the form of a loving kiss.
As Season 4 opens it is revealed that with Sky now being the King of Eraklyon, Bloom rarely has time to see him. When the Specialists arrive at Alfea to meet their girlfriends, Bloom feels sad that Sky is not there. Her attitude quickly changes as Sky is revealed to be hiding in the Specialists' ship. Their reunion is cut short as the Winx prepare to depart for Earth to find the last terrestrial fairy of Earth.
After the Winx set up their Love & Pet shop in Gardenia, Bloom's ex-boyfriend Andy shows up. He invites Bloom and the Winx to see his band perform at the Frutti Music Bar. Around the same time, Sky and the Specialists arrive in Gardenia under secret orders by Faragonda to help the Winx. Bloom, not knowing that Sky is in Gardenia spying on her, is seen hanging around with Andy. After seeing Bloom kiss Andy out of thanks, Sky assumes that Bloom still has really strong feelings for him and gets jealous. After fighting the Wizards of the Black Circle, Sky mentions to Bloom the Specialists' orders to help the Winx but also says he saw her with Andy. Bloom gets angry at him that he didn't trust her and for spying on her. She storms off with the rest of the Winx.
When the Winx fix up their apartment, Andy and his band stop by to see how its going. Stella mentions to Bloom that Andy is still into her which Bloom is surprised about. Sky and the Specialists (taking advice from Mitzi) appear sometime later to find the Winx with Andy and his group. Andy wanting to relieve the tension between everyone leaves but invites the Winx and Specialists to see his band play at the Frutti Music Bar. Sky then confronts Bloom about how close she and Andy are and storms off with the rest of the Specialists.
The two are seemingly at odds with each other at times, but they later reconcile after Bloom gets her Believix form and abilities.
Coming Soon....The Spill, Sky shows up with new changed hairstyle. Bloom appreciates the change. However, he plans to give her Pendant of Eraklyon two times before he finally lost it in a rescue action at oil rig. In that case, an old omen says if the crowned prince of Eraklyon loses the pendant,it means that he will never be happy with the girl he loves. From that time, Sky starts to avoid Bloom. Ultimately with his sacrifice for Bloom, and gets amnesia. From that moment, he treats Bloom like a stranger. In The Sirenix Book, he still refuses to remember anything and eventually dismiss her during their walk.
In Secret of the Ruby Reef, Sky accompanied Bloom, Musa and Tecna in thier mission in saving Gardenia's Ocean. Later on, Bloom tells her to fight the sea monsters but doesn't know how to use a sword but later, he regained his memories and finally gives the pendant to Bloom.
more coming soon...