Lady Gaga sells herself as a lust object? I thought she was selling herself as being batshit insane.
Per the main topic, a few points:
1) It's not wrong to say someone who posts their photo online is attractive. The last time I posted my photo online (not here), some gay guy PM'ed a complement/invitation to reciprocate. I wasn't interested, not being gay, but there was nothing that he did wrong. I thanked him for the remark and moved on.
2) It's not even wrong to try and ask someone online out on a date, IF AND ONLY IF you have met a few conditions first. Don't go out of your way to make this (or any forum) your personal dating site. In fact, don't ask anyone out until you're already friends. No woman here wants to log in and see a half dozen solicitations each day from random guys. Keep it natural. Don't be the lame internet version of the lame guy in the bar that asks 2 dozen women what their sign is until he gets a bite.
3) There's a line you can cross in #1 & 2, and that's generally the same line that exists in real life. No always means no. No creepy or crass comments like "nice boobs" or bizzare pseudo-compliments like "nice pupils". That's universal, no matter what your fetish is. Finally, if someone wants to see your junk, they'll ask. Never EVER volunteer that information.
4) Just because someone has a feminine symbol under their name, you don't not need to, and should not make a comment on that unless solicited. This ties into #1-3. You're not going to win any points from her. The "there are no girls on the internet" joke is tired and cliched (read: NOT FUNNY). And it makes you look like a 13 year old virgin who has issues talking to girls. Also, the phrase "you're just saying that cuz you're a girl" (NOTE: "You're" will almost certainly be spell "ur" or "your" in real life examples) is not an acceptable rebuttal. Learn how to argue properly.
5) Don't get bent out of shape when someone uses the word "bitch" or any other gender-specific slur (unless it's directed at you, then by all means be rightfully pissed). It's no more sexist than calling someone an asshole. Why? Because while in theory everyone can be called an asshole, in reality, 99% of the time a man is on the receiving end of that remark. That's almost certainly a higher percentage than "bitch" as men get called that by other men all the time. That goes for "jerk" "pig" "punk" and the myriad of terms prefixed with "ass." Almost all insults are gender specific whether you realize it or not. Don't get on a high horse when one gets used against your team.
6) Sole exception to #5: the C-bomb. Women really really hate that and very, very few deserved to be called something that will upset them that much. I've never used it and plenty of women have made me angry over the years. You don't need to use it either. Shove that one into the nuclear arsenal in case of Armageddon and don't pull it out a day before. Even on Judgement Day, I will assure you it will only make the situation worse.
7) #5 does not give you the right to go around calling people whores and sluts. While, generally, you really mean they're an unpleasant person that happens to be female, it's still extremely rude. Ladies, don't go around calling men pigs and dicks either for the same reason. You all can come up with better ways to describe horrible, no-talent, tone-deaf, stupid-named, one-trick, vain hacks such as Lady Gaga. (See?) On the other hand, if someone is whoring them selves in a non-literal manner, you can still call that out under Rule #5.
8) Sole exception to #7: specific individuals who were your partner and cheated on you with someone else. You have full clearance to call them a two-timing whoring slut of a pig. You do not get to blame the other 3 billion people who happen to match your ex's gender. Just the one.
9) No topless avatars, or skimpy clothed models. Actors/actresses in your favorite movies and shows are acceptable if they're in character or costume. Why? I'm sure you're interesting enough of a person that you can pick something that represents you much better than some Hollywood star(let) that you'll never even meet, never mind bed. Plus, the rest of don't really care who you think is hot.
