Being the new student at Degrassi Community School, Declan Coyne gained a reputation as a player, as he was popular among girls of the school. Trish was not immune to his charm, and the two began dating off-screen after their Chemistry class. However, in the middle of their short-term relationship, Declan began pursuing Holly J. Sinclair, as he had become infatuated with her. Declan ended up breaking it off with Trish in favor of Holly J., and Trish went on to date Ethan McBride, a member of the JV basketball team.
Season 9In Waiting for a Girl Like You, Declan begins to court Holly J. for a date while still dating Trish. Holly J. tells him that she isn't his type and calls Trish "ditzy," leading Declan to defend her, saying that she is very sweet. Holly J. proceeds to call her a "house plant," meaning she is low maintenance, the total opposite of her. The next day, Declan almost wins Holly J. over with his tales of his adventures in foreign countries at lunch, before Trish interrupts the two of them, asking him if they are still on for their date that night. She realizes Declan is flirting with another girl, and sarcastically asks if he was telling the "Dali Lama" story, revealing that Declan uses the stories to pick up girls. Trish walks away angrily, leaving Holly J. and Declan alone at the table.
In class, Declan tries to talk to Holly J. to apologize about having plans with Trish, leading to Sav Bhandari to loudly whisper, "Dude! You're still with Trish?" Declan tells her that he plans to break up with Trish face to face, and Holly J. decides to give him the silent treatment.
Later, while on a date Holly J., Declan receives a text from Trish, reading "Come and see me later? xoxo." Holly J. asks who the message was from, but he tells it was from no one, proceeding to put his phone back in his pocket without responding to the text message. He then cheats on Trish by kissing Holly J.
In Somebody, Declan breaks up with Trish, saying they got into their relationship too fast and that she is an amazing girl and he doesn't want to limit her. He tells him he wants her to feel free, but she cuts him off, saying, "Nice line," before telling him that he is the player everyone says he is. She walks off, and he tells Holly J. that he thinks she took their break up well.
In the Degrassi Mini Searching for Sinder3lla, Declan and Trish are dating. She kisses him goodbye, telling him that she'll back soon and to keep his lips warm for her. Sav questions him, "So, you and Trish, eh?", sounding impressed. Declan calls Trish exquisite, and Sav geekily says that she is exquisitely exquisite. Declan tells him how they met in Chemistry class, saying their eyes met over the flame of the Bunsen burner and she asked for his number after class. Sav is amazed that he picked her up with just a look, as it takes him days of hard work to please his girlfriend, Anya MacPherson.
Ignoring Sav, Declan is amazed at the user profile of the girl who had been sitting at the computer before him, who had forgotten to log out. He says that this girl is perfect for him, leading Sav to ask about "Exquisite Trish," but Declan ignores him again.
Later, after getting the freshmen to assist him in finding his dream girl online, Declan asks, "So, that's it? No girl for me?" Sav responds, "Except your current girlfriend..."
Declan gets Sav to ask Chantay Black about the "Sinder3lla," as he already has a girlfriend, Trish, and no one would believe that Sav is looking "to upgrade." After Declan discovers Holly J. is the mystery girl after seeing her pencil bag with "Sinder3lla" decorated across it, Trish approaches him again and hugs him, but Declan stares after Holly J. longingly.
- Start Up: Between Beat It (1) (907) and Waiting for a Girl Like You (909)
- Broke Up: Somebody (910)
- Reason: Declan developed feelings for Holly J.