Eikko (Erik) Petteri Koskinen is a supporting character in The Heir and The Crown and love interest of Eadlyn Schreave. He was hired as the translator of the Selected Henri Jaakoppi during Princess Eadlyn's Selection, because Henri is from Swendway and was only able to speak Finnish fluently with very little English.
Erik is a first generation Swendish to be born in Illéa, but his parents are trying to hold onto their old customs, so they live in a small Swendish community in Kent. When Henri was selected, his family put out a call for a reliable translator and Erik submitted his résumé, flew to Sota, and was subsequently hired. Even though he met Henri only a week before the Selection started, he told Eadlyn that he felt like he'd known Henri for much longer.
He has interacted with Eadlyn and a spark had started. He had saved Eadlyn, during a fight between Burke, Fox, Henri, and Kile. He took her to her bedroom and kindly comforted her, so Eadlyn discovered something new in Erik, something beautiful. He offered to become her friend and she gladly accepted. It was later revealed by Eadlyn that she feel for him during this moment.
At some point, Eadlyn realized that the feelings she actually had for Erik were romantic. After her coronation, they confessed their love for each other, but unfortunately could not be together due to the fact that Erik was not there as one of the Selected and therefore not a viable candidate. Instead, they had secret dates during Eadlyn's Selection. However, in the end of The Crown, Eadlyn decided to follow her heart and she announced publicly during The Report that she was in love with Erik. She proposed marriage to him and he happily accepted.
After their marriage, they had a daughter named Kerttu and they are expecting a second child.
Eadlyn mentions that "Erik’s eyes were clear and blue, a stark contrast to his dark hair".
When Eadlyn first met him, she thought he was "slightly drabber" than Henri. She also mentions that "he dressed differently, walked at a slower pace, and even carried himself a little lower" that the other Suitors. He has a "shy smile".
However, during a party, Eadlyn mentioned: "Erik came down the hall in the smartest suit I’d seen him in to date. His hair was neater than usual, slightly slicked back. He looked taller, prouder. My jaw fell open at the change. He looked positively gorgeous."
- "Why would you try to be her [Camille] when Eadlyn is more than enough?" — Erik to Eadlyn
- Erik: "I couldn't run a country." Eadlyn:"Trust me, if I can learn to do it, anybody could."
- "I remembered the feeling of my first date with Hale, how I felt when I was sure he'd peel everything back and had seen the real me. This time, I felt like I was on the other side of that, looking past duty and worry and rank, seeing the true heart of a person. And his [Erik's heart] was so beautiful." — Eadlyn about Erik
- "I think aggression is a sign of weakness. I’m always more impressed when people can end something with words. [...] Maybe that’s why language became so important to me. My father, he always used to say ‘Eikko, words are weapons. They are all you need.’" — Erik to Eadlyn
- "I tilted my head, really looking at him. It felt like something had just happened, but I didn't know what it was. Erik, without knowing me, had done so much right. He pulled me away before I made the situation worse, got me to solitude before I lost control of my emotions, and stayed with me, listening to my worries and making everything better with his words. There were scores of people on call, ready to do whatever I asked. It was so funny to me that with him I didn't even have to ask." — Eadlyn about Erik
- "He [Erik] rubbed his thumb against the back of my hand, the tiniest movement. And I could sense we were both wondering what would have happened if his name had been in one of those baskets. Maybe he'd be one of the contenders, maybe he wouldn't have been picked at all... it was hard to say if the risk would have been worth it in the end." — Eadlyn about Erik
- "When I came up the second time, laughing, I spotted Erik over his [Henri's] shoulder. I could have been wrong, but his shy smile looked a little sad." — Eadlyn about Erik while she was dancing with Henri
- "Erik came down the hall in the smartest suit I'd seen him in to date. His hair was neater than usual, slightly slicked back. He looked taller, prouder. My jaw fell open at the change. He looked positively gorgeous." — Eadlyn about Erik
- "Are you okay, Your Highness?' His [Erik's] voice was so tender but, mercifully, lacking pity." — Erik to Eadlyn
- "I'd thought this to myself before, but I'd never admitted it to anyone. I wasn't sure how Erik managed to make me want to confide this in him." — Eadlyn about Erik
- "Henri leaned forward on his bench, his curls flopping over his eyes; and I was happy to see that, even though he didn't need to come, Erik stood beside him." — Eadlyn about Henri and Erik
- "I kept worrying that Erik felt like an outcast. He certainly worked to separate himself from the Selected. He dressed differently, walked at a slower pace, and even carried himself a little lower." — Eadlyn about Erik
- "Erik shook his head at me, and I was strangely comforted. At least someone seemed to understand how I was feeling." — Eadlyn about Erik
- His name, "Erik," is the closest translation of "Eikko" in English.
- His name means "eternal ruler".
- He lives alone. He cooks for himself, and he loves all the traditional Swendish foods. Like Henri, one of his favorite sweets is korvapuusti (Cinnamon rolls, or "a slap on the ear"). They also both like a soup with potatoes and fish.
- He bites his nails when he is nervous.