Saw my best friend suck himself

After not having seen my best friend in over a year I went ‘round his house and stayed over night. We had dinner, chilled in the pool and had a couple of beers.
It was getting late so we decided to get out and change to go to bed but because I have curly hair I told him I wanted to have a shower first ( to get the chlorine out ).
Anyways after getting out the shower I went to his room we were both going to sleep in and he wasn’t there. I called him but no answer. So I went ‘round the house to see if I could find him and after having gone around the house there was no sign of him except for his dad’s room which was locked. I assumed it was his dad ( who was supposedly on a night out ) and that he’d come back early. I ended up giving up and went back to his room to wait for him when I remembered he showed me how him and his dad had set up their house as a complete “smart house” or whatever you call it and how you can pretty much control everything from your device, including cameras.
So I decided to log into his ipad, not in a weird way but just to see if I could see him somewhere I hadn’t been in one of the cameras, and I received the shock of my life. My best friend was in his dad’s room, completely naked, on the bed sucking his own cock. Not only this, but because of the position he was in, he had his ass spread and was fingering himself.
Nobody knows, but I’m bi, and up until this point I thought my best friend was 100% straight.
Initially, in shock, I turned it off immediately and pretended I didn’t see anything. But then after five minutes and still nothing I logged back in and he was still going. So, in his bed, I took my shorts off and started jerking off too. 10 minutes later my friend came in his mouth and I came all over myself but what I failed to even think about was my friend, having came in his mouth, had no need to clear up. I however, now completely naked too, had come all over myself.
So as quick as I could I ran to the toilet and cleared myself up. After, I made my way back and my best friend was looking at his phone in bed. He was in his underwear and I was in shorts, which is chill because its summer and its hot and we are comfortable with one another. But as I got close I froze. In the middle of the bed was a massive ammount of my cum I’d forgotten to clear up. I ddin’t know what to do, so I said nothing and just got in to bed. My best friend pretended not to have noticed as well, but after deciding to go to sleep he rolled over and layed directly on top of it.
When morning came, none of us said anything, but he had a new pair of underwear on, so I knew it wasn’t all a dream lol.