My (23F) boyfriend (24M) has waifus and it's destroying our relationship. How should I bring it up?

Throwaway account.<br><br>My boyfriend and i have been together for 10 months. Things have been going great! We have our little tiffs but we always manage to communicate through it. <br><br>However he watches a lot of anime and plays a lot of video games and I know a little bit about waifus. He sometimes jokes that certain video game characters or anime characters are his "second wife" and "waifu" and I know enough about the terminology to know that isn't a great thing. To my knowledge though he doesn't have a "waifu".<br><br>That was until a couple days ago. He had left his phone on the coffee table and I happened to see a text from his best mate come in. His best mate has a fiance (let's call her Jenny) and sometimes when Jenny is around, she'll engage in these waifu jokes with my boyfriend. She will go along with the jokes about her being second choice to "Asuna" (a character from sword art online) or how she's okay with my boyfriend having a second wife as long as it's asuna and she's happy to be second. <br><br>The text I saw was from this best mate's fiance, but it was different though. It said something along the lines of "I know asuna is your number 1 but don't think we won't be having some couple dates". I'm sure if I looked through their chat history I would have seen more of this. <br><br>Then I felt bad and put the phone down. But inside I'm absolutely reeling. I feel like I've been punched in the gut. I'm just so confused as to why he has to do this? I know he loves me, and he shows me that he loves me everyday, but why can't he just be happy with me? Why does he need asuna? Asuna is a cartoon! I'm a real woman and I can do anything for him that Asuna can. Just by looking at her I know I can outdo her in looks and personality! But still he chooses her over me. Still he wants her to be his wife. <br><br>So I've just been bottling this up inside. I've been trying to act normally. But he keeps making these little comments about how he wishes he could do this or that with me but he can't in real life. Like the other day we were having sex and he was going "I wish you could actually feel pain right now" but I couldn't. Then he apologised but the damage was done. I just feel like I can never satisfy him. That he will always want another and I will never be enough for him. <br><br>I don't know how to talk to him about this. I feel like he'll just deny it and say I'm being crazy. Or he'll say that it's just a bit of fun. But I just feel like it's so disrespectful to me and I don't know how to say that without sounding like I'm being a bitch! <br><br>I'm seriously considering just breaking up with him. I don't want to be second choice to some cartoon!