It's like those first few seconds when you wake up, but less confusing, like you're suddenly entering a different reality again... something familiar, or something shocking, depending on the hit. And just like when you first wake up, sometimes the words trail out of your mouth without you even intending to speak them, like you're finishing a sentence you said in a distant dream. And similar to in your dreams, you have what seems like a fuzz of uncertainty around everything that happens, not everything makes sense but you don't really mind at all. You don't mind about much, it's hard to force emotions when your senses are dulled to relaxation. It's like waking up in the middle of the night to find that the person you usually sleep next to isn't there this evening, everything moves slowly and people come in and out without you even realising. And your eyes are loose and tranquil, a sleep needed for slumber.
So, we take drugs to feel like we are asleep. And once you've felt that life, you don't want to be awake anymore. Real experiences seem so slow and dismal to the mind.